Just did some tests -- opening an older session where I used to run Kontakt in standalone but now run Kontakt 4 in VE Pro, when I load a patch it takes about three minutes of spinning beach ball before the patch appears. Starting a session from scratch I can't recreate the problem; patches load as normal.
If I can't reproduce it, I can't really call it a bug or an incompatibility -- just a mystery.
(FYI: That's 10.5.8 on Quad 2x2.66 Mac Pro, Pro Tools 8.0.1 and Kontakt 4.)