Hi,
the folders, which contain the effects in the interface, cannot be expanded. They don't have a '+' or something and (double)clicking on them has no effect.
However, entering a letter in the filterbox does show the effects (i.e. if I enter 'a' I can see all effects containing an 'a').
Don't know if this problem is related to qt/kdelibs or kdenlive though.

sorry, I forgot to add that I use kdenlive in debian, from the repos (0.7.8 with kde 4.4.5).
I have attached a pic for better understanding of what I mean.