diff --git a/spine-csharp/src/IkConstraintData.cs b/spine-csharp/src/IkConstraintData.cs
index 28d0cd3b0..7c923e712 100644
--- a/spine-csharp/src/IkConstraintData.cs
+++ b/spine-csharp/src/IkConstraintData.cs
@@ -35,9 +35,9 @@ namespace Spine {
 	public class IkConstraintData : ConstraintData {
 		internal ExposedList<BoneData> bones = new ExposedList<BoneData>();
 		internal BoneData target;
-		internal int bendDirection = 1;
+		internal int bendDirection;
 		internal bool compress, stretch, uniform;
-		internal float mix = 1, softness;
+		internal float mix, softness;
 
 		public IkConstraintData (string name) : base(name) {
 		}
diff --git a/spine-csharp/src/PhysicsConstraint.cs b/spine-csharp/src/PhysicsConstraint.cs
index bcea4092e..109e79ba3 100644
--- a/spine-csharp/src/PhysicsConstraint.cs
+++ b/spine-csharp/src/PhysicsConstraint.cs
@@ -156,14 +156,16 @@ namespace Spine {
 					ux = bx;
 					uy = by;
 				} else {
-					float a = this.remaining, i = inertia, t = data.step, f = skeleton.data.referenceScale;
+					float a = this.remaining, i = inertia, q = data.limit, t = data.step, f = skeleton.data.referenceScale;
 					if (x || y) {
 						if (x) {
-							xOffset += (ux - bx) * i;
+							float u = (ux - bx) * i;
+							xOffset += u > q ? q : u < -q ? -q : u;
 							ux = bx;
 						}
 						if (y) {
-							yOffset += (uy - by) * i;
+							float u = (uy - by) * i;
+							yOffset += u > q ? q : u < -q ? -q : u;
 							uy = by;
 						}
 						if (a >= t) {
@@ -190,7 +192,10 @@ namespace Spine {
 						float ca = (float)Math.Atan2(bone.c, bone.a), c, s, mr = 0;
 						if (rotateOrShearX) {
 							mr = (data.rotate + data.shearX) * mix;
-							float dx = cx - bone.worldX, dy = cy - bone.worldY, r = (float)Math.Atan2(dy + ty, dx + tx) - ca - rotateOffset * mr;
+							float dx = cx - bone.worldX, dy = cy - bone.worldY;
+							float r = (float)Math.Atan2((dy > q ? q : dy < -q ? -q : dy) + ty, (dx > q ? q : dx < -q ? -q : dx) + tx) - ca
+								- rotateOffset * mr;
+
 							rotateOffset += (r - (float)Math.Ceiling(r * MathUtils.InvPI2 - 0.5f) * MathUtils.PI2) * i;
 							r = rotateOffset * mr + ca;
 							c = (float)Math.Cos(r);
diff --git a/spine-csharp/src/PhysicsConstraintData.cs b/spine-csharp/src/PhysicsConstraintData.cs
index 3ff48c754..4db8a2185 100644
--- a/spine-csharp/src/PhysicsConstraintData.cs
+++ b/spine-csharp/src/PhysicsConstraintData.cs
@@ -35,7 +35,7 @@ namespace Spine {
 	/// </summary>
 	public class PhysicsConstraintData : ConstraintData {
 		internal BoneData bone;
-		internal float x, y, rotate, scaleX, shearX;
+		internal float x, y, rotate, scaleX, shearX, limit;
 		internal float step, inertia, strength, damping, massInverse, wind, gravity, mix;
 		internal bool inertiaGlobal, strengthGlobal, dampingGlobal, massGlobal, windGlobal, gravityGlobal, mixGlobal;
 
@@ -51,6 +51,7 @@ namespace Spine {
 		public float Rotate { get { return rotate; } set { rotate = value; } }
 		public float ScaleX { get { return scaleX; } set { scaleX = value; } }
 		public float ShearX { get { return shearX; } set { shearX = value; } }
+		public float Limit { get { return limit; } set { limit = value; } }
 		public float Inertia { get { return inertia; } set { inertia = value; } }
 		public float Strength { get { return strength; } set { strength = value; } }
 		public float Damping { get { return damping; } set { damping = value; } }
diff --git a/spine-csharp/src/SkeletonBinary.cs b/spine-csharp/src/SkeletonBinary.cs
index 569ff53e0..3a9b2b83b 100644
--- a/spine-csharp/src/SkeletonBinary.cs
+++ b/spine-csharp/src/SkeletonBinary.cs
@@ -242,14 +242,14 @@ namespace Spine {
 				for (int ii = 0; ii < nn; ii++)
 					constraintBones[ii] = bones[input.ReadInt(true)];
 				data.target = bones[input.ReadInt(true)];
-				data.mix = input.ReadFloat();
-				data.softness = input.ReadFloat() * scale;
 				int flags = input.Read();
 				data.skinRequired = (flags & 1) != 0;
 				data.bendDirection = (flags & 2) != 0 ? 1 : -1;
 				data.compress = (flags & 4) != 0;
 				data.stretch = (flags & 8) != 0;
 				data.uniform = (flags & 16) != 0;
+				if ((flags & 32) != 0) data.mix = (flags & 64) != 0 ? input.ReadFloat() : 1;
+				if ((flags & 128) != 0) data.softness = input.ReadFloat() * scale;
 				o[i] = data;
 			}
 
@@ -266,18 +266,19 @@ namespace Spine {
 				data.skinRequired = (flags & 1) != 0;
 				data.local = (flags & 2) != 0;
 				data.relative = (flags & 4) != 0;
-				data.offsetRotation = input.ReadFloat();
-				data.offsetX = input.ReadFloat() * scale;
-				data.offsetY = input.ReadFloat() * scale;
-				data.offsetScaleX = input.ReadFloat();
-				data.offsetScaleY = input.ReadFloat();
-				data.offsetShearY = input.ReadFloat();
-				data.mixRotate = input.ReadFloat();
-				data.mixX = input.ReadFloat();
-				data.mixY = input.ReadFloat();
-				data.mixScaleX = input.ReadFloat();
-				data.mixScaleY = input.ReadFloat();
-				data.mixShearY = input.ReadFloat();
+				if ((flags & 8) != 0) data.offsetRotation = input.ReadFloat();
+				if ((flags & 16) != 0) data.offsetX = input.ReadFloat() * scale;
+				if ((flags & 32) != 0) data.offsetY = input.ReadFloat() * scale;
+				if ((flags & 64) != 0) data.offsetScaleX = input.ReadFloat();
+				if ((flags & 128) != 0) data.offsetScaleY = input.ReadFloat();
+				flags = input.Read();
+				if ((flags & 1) != 0) data.offsetShearY = input.ReadFloat();
+				if ((flags & 2) != 0) data.mixRotate = input.ReadFloat();
+				if ((flags & 4) != 0) data.mixX = input.ReadFloat();
+				if ((flags & 8) != 0) data.mixY = input.ReadFloat();
+				if ((flags & 16) != 0) data.mixScaleX = input.ReadFloat();
+				if ((flags & 32) != 0) data.mixScaleY = input.ReadFloat();
+				if ((flags & 64) != 0) data.mixShearY = input.ReadFloat();
 				o[i] = data;
 			}
 
@@ -291,10 +292,12 @@ namespace Spine {
 				for (int ii = 0; ii < nn; ii++)
 					constraintBones[ii] = bones[input.ReadInt(true)];
 				data.target = slots[input.ReadInt(true)];
-				data.positionMode = (PositionMode)Enum.GetValues(typeof(PositionMode)).GetValue(input.ReadInt(true));
-				data.spacingMode = (SpacingMode)Enum.GetValues(typeof(SpacingMode)).GetValue(input.ReadInt(true));
-				data.rotateMode = (RotateMode)Enum.GetValues(typeof(RotateMode)).GetValue(input.ReadInt(true));
-				data.offsetRotation = input.ReadFloat();
+				int flags = input.Read();
+				data.positionMode = (PositionMode)Enum.GetValues(typeof(PositionMode)).GetValue(flags & 1);
+				data.spacingMode = (SpacingMode)Enum.GetValues(typeof(SpacingMode)).GetValue((flags >> 1) & 3);
+				data.rotateMode = (RotateMode)Enum.GetValues(typeof(RotateMode)).GetValue((flags >> 3) & 3);
+				if ((flags & 128) != 0) data.offsetRotation = input.ReadFloat();
+
 				data.position = input.ReadFloat();
 				if (data.positionMode == PositionMode.Fixed) data.position *= scale;
 				data.spacing = input.ReadFloat();
@@ -318,14 +321,14 @@ namespace Spine {
 				if ((flags & 8) != 0) data.rotate = input.ReadFloat();
 				if ((flags & 16) != 0) data.scaleX = input.ReadFloat();
 				if ((flags & 32) != 0) data.shearX = input.ReadFloat();
+				data.limit = ((flags & 64) != 0 ? input.ReadFloat() : 500) * scale;
 				data.step = 1f / input.ReadUByte();
 				data.inertia = input.ReadFloat();
 				data.strength = input.ReadFloat();
 				data.damping = input.ReadFloat();
-				data.massInverse = input.ReadFloat();
+				data.massInverse = (flags & 128) != 0 ? input.ReadFloat() : 1;
 				data.wind = input.ReadFloat();
 				data.gravity = input.ReadFloat();
-				data.mix = input.ReadFloat();
 				flags = input.Read();
 				if ((flags & 1) != 0) data.inertiaGlobal = true;
 				if ((flags & 2) != 0) data.strengthGlobal = true;
@@ -334,6 +337,7 @@ namespace Spine {
 				if ((flags & 16) != 0) data.windGlobal = true;
 				if ((flags & 32) != 0) data.gravityGlobal = true;
 				if ((flags & 64) != 0) data.mixGlobal = true;
+				data.mix = (flags & 128) != 0 ? input.ReadFloat() : 1;
 				o[i] = data;
 			}
 
@@ -447,7 +451,7 @@ namespace Spine {
 				string path = (flags & 16) != 0 ? input.ReadStringRef() : null;
 				uint color = (flags & 32) != 0 ? (uint)input.ReadInt() : 0xffffffff;
 				Sequence sequence = (flags & 64) != 0 ? ReadSequence(input) : null;
-				float rotation = input.ReadFloat();
+				float rotation = (flags & 128) != 0 ? input.ReadFloat() : 0;
 				float x = input.ReadFloat();
 				float y = input.ReadFloat();
 				float scaleX = input.ReadFloat();
@@ -880,17 +884,20 @@ namespace Spine {
 			for (int i = 0, n = input.ReadInt(true); i < n; i++) {
 				int index = input.ReadInt(true), frameCount = input.ReadInt(true), frameLast = frameCount - 1;
 				IkConstraintTimeline timeline = new IkConstraintTimeline(frameCount, input.ReadInt(true), index);
-				float time = input.ReadFloat(), mix = input.ReadFloat(), softness = input.ReadFloat() * scale;
+				int flags = input.Read();
+				float time = input.ReadFloat(), mix = (flags & 1) != 0 ? ((flags & 2) != 0 ? input.ReadFloat() : 1) : 0;
+				float softness = (flags & 4) != 0 ? input.ReadFloat() * scale : 0;
 				for (int frame = 0, bezier = 0; ; frame++) {
-					int flags = input.Read();
-					timeline.SetFrame(frame, time, mix, softness, input.ReadSByte(), (flags & 1) != 0, (flags & 2) != 0);
+					timeline.SetFrame(frame, time, mix, softness, (flags & 8) != 0 ? 1 : -1, (flags & 16) != 0, (flags & 32) != 0);
+
 					if (frame == frameLast) break;
-					float time2 = input.ReadFloat(), mix2 = input.ReadFloat(), softness2 = input.ReadFloat() * scale;
-					switch (input.ReadUByte()) {
-					case CURVE_STEPPED:
+					//float time2 = input.ReadFloat(), mix2 = input.ReadFloat(), softness2 = input.ReadFloat() * scale;
+					flags = input.Read();
+					float time2 = input.ReadFloat(), mix2 = (flags & 1) != 0 ? ((flags & 2) != 0 ? input.ReadFloat() : 1) : 0;
+					float softness2 = (flags & 4) != 0 ? input.ReadFloat() * scale : 0;
+					if ((flags & 64) != 0)
 						timeline.SetStepped(frame);
-						break;
-					case CURVE_BEZIER:
+					else if ((flags & 128) != 0) {
 						SetBezier(input, timeline, bezier++, frame, 0, time, time2, mix, mix2, 1);
 						SetBezier(input, timeline, bezier++, frame, 1, time, time2, softness, softness2, scale);
 						break;
diff --git a/spine-csharp/src/SkeletonJson.cs b/spine-csharp/src/SkeletonJson.cs
index 3a80544be..0da0f2121 100644
--- a/spine-csharp/src/SkeletonJson.cs
+++ b/spine-csharp/src/SkeletonJson.cs
@@ -303,6 +303,7 @@ namespace Spine {
 					data.rotate = GetFloat(constraintMap, "rotate", 0);
 					data.scaleX = GetFloat(constraintMap, "scaleX", 0);
 					data.shearX = GetFloat(constraintMap, "shearX", 0);
+					data.limit = GetFloat(constraintMap, "limit", 500) * scale;
 					data.step = 1f / GetInt(constraintMap, "fps", 60);
 					data.inertia = GetFloat(constraintMap, "inertia", 1);
 					data.strength = GetFloat(constraintMap, "strength", 100);
diff --git a/spine-csharp/src/package.json b/spine-csharp/src/package.json
index f521abc9a..31d69a5fc 100644
--- a/spine-csharp/src/package.json
+++ b/spine-csharp/src/package.json
@@ -2,7 +2,7 @@
 	"name": "com.esotericsoftware.spine.spine-csharp",
 	"displayName": "spine-csharp Runtime",
 	"description": "This plugin provides the spine-csharp core runtime.",
-	"version": "4.2.13",
+	"version": "4.2.14",
 	"unity": "2018.3",
 	"author": {
 		"name": "Esoteric Software",