transitions not working as expected

Hi, I've got a problem during editing and don't know if it's a bug or if it's a feature :)

Imagine I have two video tracks, the lower one (track 1) with an image clip where I zoom into the image with the help of the PiP transition. The upper track (track 0) contains another image clip that is faded in and out again.

What is strange for me, however, is that the zoom of the lower track is applied to the upper one as well, although I want to have it in original size, just with the fade.

When I remove the crossfade transition from the upper clip, it appears in its original size, and the PiP transition of the lower clip has no effect on the upper clip. As soon as I apply the crossfade transition to the upper clip, however, the PiP transition that belongs to the lower clip extends its effect to the upper clip (that should only have the crossfade transition) as well.

I find this behaviour rather disturbing, and I am not really sure if it's the correct behaviour or if I should file a bug.
BTW, the post here may be a more general description of this report:

My kdenlive version is svn-1801.

Thanks for your advice!