I haven't tested the program on Vista yet, as I use XP instead. It should work without problems tough, as the APP model hasn't changed.
That error is because you must be an admin to install the program. If not, part of it does not installs correctly (like that DLL, for example).
Once I can have some free time, I will launch the new version with a much more complete installer. I've been promising the new version a lot, but i haven't found the time to write it:(
(If you find any mistake in my English, please let me know via a PM)
(Really, I speak terrible English, so please, tell me if I make mistakes. I'd like to improve it a bit )