Ok, I'll try to explain here how to transfer animation from the old KFE to the new AE. If you're not familiar with the new architecture you might find it a little tricky to do, however once you get it, it's really not that difficult. In this example I'll use an animation path seeing as that was the original question.
First make a copy of the object that you want to animate. Then make sure the bridge is set to "ON".
Now switch to the model view and open a KFE window. I like to dock it at the bottom so I can see both the old and new animation windows at the same time. To dock it, hold Ctrl and drag the window to where you want it.
Next draw the animation path using the "Copy" object.
Now switch the AE window to 2D (black button in upper right corner of the window). Find the "original" object and "copy" object nodes in the 2d window. Click on the "Exp" or "default" tab on the nodes (just make sure you can see the "matrix" inputs and "wldmatrix" outputs on the nodes). Position them as shown in the image below. Click and drag on the "WldMatrxix" output on the copy object node. Drag the link into the "Matrix" input on the original object node and let go. A link will be made. This will take the Location, Rotation, and Scale information from the copy object and send it into the original. So the original object will now exactly mimic the animation of the copy object.
Next change the 2d window back to 4d (animation view). Make sure that both the old and new animation windows are set to the beginning. Then make sure the original object is selected and hit the record button in the new AE. This will begin to record the original object in the AE. Now move the scrubbers of both the new AE and old KFE to the next keyframe that the path created in the old KFE. Again, click the record button in the new AE to record that keyframe. Continue on manually matching up the scrubbers in both animation windows and recording the keyframes into the new AE.
When you're done, you can set the window back to 2d and disconnect the link made earlier. This will give control back to the AE.
Now you can delete the copy object and turn the bridge back off. You should now have the object animated with keyframes in the new AE. I know that this method isn't ideal, but until animation paths get implemented in the new workspace side this can be used as a workaround. It might seem difficult at first, but once you get going it's really not too bad.
hth
Edit: Instead of KFE I probably should have said Scene Editor. Anyway, same difference.
#prodigy: Thanks Trueblue