diff --git a/src/main/java/eu/crushedpixel/replaymod/interpolation/GenericLinearInterpolation.java b/src/main/java/eu/crushedpixel/replaymod/interpolation/GenericLinearInterpolation.java
index af3e9cbf..8f6fc077 100755
--- a/src/main/java/eu/crushedpixel/replaymod/interpolation/GenericLinearInterpolation.java
+++ b/src/main/java/eu/crushedpixel/replaymod/interpolation/GenericLinearInterpolation.java
@@ -30,8 +30,13 @@ public class GenericLinearInterpolation<T extends KeyframeValue> implements Inte
 
     @Override
     public void applyPoint(float position, T toEdit) {
-        if(points.isEmpty()) {
-            throw new IllegalStateException("At least one Value needs to be added for this operation");
+        if(fields == null) {
+            throw new IllegalStateException("At least one Keyframe has to be added before preparing");
+        }
+
+        if(fields.length <= 0) {
+            throw new IllegalStateException("The passed KeyframeValue class" +
+                    " has to contain at least one Field");
         }
 
         //first, get previous and next T for given position
diff --git a/src/main/java/eu/crushedpixel/replaymod/interpolation/GenericSplineInterpolation.java b/src/main/java/eu/crushedpixel/replaymod/interpolation/GenericSplineInterpolation.java
index e222dc24..0b62976e 100755
--- a/src/main/java/eu/crushedpixel/replaymod/interpolation/GenericSplineInterpolation.java
+++ b/src/main/java/eu/crushedpixel/replaymod/interpolation/GenericSplineInterpolation.java
@@ -30,10 +30,15 @@ public class GenericSplineInterpolation<T extends KeyframeValue> extends BasicSp
 
     @Override
     public void prepare() {
+        if(fields == null) {
+            throw new IllegalStateException("At least one Keyframe has to be added before preparing");
+        }
+
         if(fields.length <= 0) {
             throw new IllegalStateException("The passed KeyframeValue class" +
                     " has to contain at least one Field");
         }
+
         if(!points.isEmpty()) {
             cubics = new ArrayList<Vector<Cubic>>(fields.length);
             for (Field field : fields) {
diff --git a/src/main/java/eu/crushedpixel/replaymod/interpolation/KeyframeList.java b/src/main/java/eu/crushedpixel/replaymod/interpolation/KeyframeList.java
index c7077431..96420ddc 100644
--- a/src/main/java/eu/crushedpixel/replaymod/interpolation/KeyframeList.java
+++ b/src/main/java/eu/crushedpixel/replaymod/interpolation/KeyframeList.java
@@ -153,15 +153,7 @@ public class KeyframeList<K extends KeyframeValue> extends ArrayList<Keyframe<K>
         K toApply = (K) first().getValue().newInstance();
 
         if(previousCallLinear != (Boolean)linear) {
-            previousCallLinear = linear;
-
-            interpolation = linear ? new GenericLinearInterpolation<K>() : new GenericSplineInterpolation<K>();
-
-            for(Keyframe<K> keyframe : this) {
-                interpolation.addPoint(keyframe.getValue());
-            }
-
-            interpolation.prepare();
+            recalculate(linear);
         }
 
         interpolation.applyPoint(pathPosition, toApply);
@@ -169,6 +161,24 @@ public class KeyframeList<K extends KeyframeValue> extends ArrayList<Keyframe<K>
         return toApply;
     }
 
+    /**
+     * Recalculates the underlying Interpolation instances.
+     * @param linear Whether to prepare linear or cubic interpolation
+     */
+    public void recalculate(boolean linear) {
+        previousCallLinear = linear;
+
+        if(isEmpty()) return;
+
+        interpolation = linear ? new GenericLinearInterpolation<K>() : new GenericSplineInterpolation<K>();
+
+        for(Keyframe<K> keyframe : this) {
+            interpolation.addPoint(keyframe.getValue());
+        }
+
+        interpolation.prepare();
+    }
+
     /**
      * Returns a value between 0 and 1, representing the number that should be passed
      * to Interpolation#getValue() calls on this list of Keyframes.
diff --git a/src/main/java/eu/crushedpixel/replaymod/replay/ReplayHandler.java b/src/main/java/eu/crushedpixel/replaymod/replay/ReplayHandler.java
index 92afff76..762cad71 100755
--- a/src/main/java/eu/crushedpixel/replaymod/replay/ReplayHandler.java
+++ b/src/main/java/eu/crushedpixel/replaymod/replay/ReplayHandler.java
@@ -579,6 +579,7 @@ public class ReplayHandler {
 
     public static void fireKeyframesModifyEvent() {
         FMLCommonHandler.instance().bus().post(new KeyframesModifyEvent(positionKeyframes, timeKeyframes));
-
+        positionKeyframes.recalculate(ReplayMod.replaySettings.isLinearMovement());
+        timeKeyframes.recalculate(ReplayMod.replaySettings.isLinearMovement());
     }
 }