Is There a Maximum Number of Effects One Can Use on a Clip?

I created a 40 second clip with 6 layers of video plus one audio (as part of a larger project). The five layers are PIPs that are themselves have many motion and video effects. Building the clip, at one point the last motion effect stopped working. My solution was to export each of the 3 x 4 PIPs with all the effects (except the motion effects) as MPEG2 Blu-ray files (m2v) and using these clips I built the final clip (where I applied the motion effects: spinning in the PIPs, etc...). This approach worked.

Questions:

1. Is there "maximum complexity" of effects in PrPro CS5, or I still have some corrupted O.S. files, or corrupted registry?
2. Working this way (until after I have done a clean O.S. install), would I degrade the quality of the Blu-ray project?
3. I am also worried how "far" I have to go back: is it possible that the other sequences I use in the full project are also corrupted? (They play well in both   PrPro and Encore and can be transcoded.)

I have been having some problems lately and eventually I have to start everything from the beginning.

I would appreciate any comment, help.

Best regards,

Laci.