I've only experienced minor problems running BFD 1.5 with Logic Pro 7.2. Since installing BFD 1.5, I can no longer start up Logic unless BFD is running - which is annoying but not totally disruptive. There is also the fact that BFD is very processor greedy as mentioned above, but again, not totally disruptive.
It's a side issue, but I note that more bugs with Logic 7 have manifested since I upgraded to Mac OSX 10.4.11, and for that reason I am very reluctant to upgrade to Leopard right now- chances are things will get worse rather than better and I will have to upgrade to Logic 8 - on and on it goes... So I'm sticking where I am cos I got work to do.
Since you've already presumably checked your hard drives(s) with a disc utility, repaired permissions, pre-bindings, directories and all that jazz, maybe the only thing left is to try reinstalling both Logic and BFD from scratch-?
I was considering upgrading to BFD2, but now I'm glad I didn't - good luck!