jnyreno... Flexi 8.5 was written for Leopard. With Snow Leopard I have noticed only 2 annoyances so far:
1. File > Export. The list of "Save as type" in the Export dialog displays "??" instead of the actual export type. However, the software will export files correctly.
2. SafeNet (hardware key) displays warning messages when launching the program. Once you click past the message, the software launches fine and is perfectly functional.
IMO- these annoyances are not big enough to keep you from upgrading to Snow Leopard... but SAi and SafeNet are working on both.