Can someone please point me in the right direction?

Recently, within the last 2 builds of RedCine, the app will no longer open on my dual quad 3.0ghz Mac Pro. It was fine, then all of a sudden, tires to open, shows black for a fraction of a second, then unexpectedly quites. I've trashed library files, reinstalled, everything i can think of. It wont open.

Fine, i moved to my dual quad pc. Basically the same setup as the Mac Pro. It used to work also. I can get into the program fine and do all my work. However I cannot save project files. I get 'failed to write file'. Fair enough, i'll just work and render it. When i render (QT, Tiff, Targa, etc). It chuggs along just fine, but renders only black frames. What's going on with this thing and how do i get my footage to render? I reeeeeaaaaly do not want to use red alert to color all this footage.

Please help.