RJARRRPCGP: JPG decompression support? I'm fairly sure 1964 0.9.9 already has that. check again mate
I've seen the 2d backgrounds in Zelda work perfectly in 1964 without rsp.dll (the JPG ones)
Linkindarf: Yes you can do that but you've still not given enough information... Read my last post, nobody can help you until you provide a bit more, like the Plugins you are using on 1964 that are "crazy" and the games name in paticular.
Emulators are a complex thing so you must provide as much information as possible.. after all! we're not all phychic!
You definatly should try taking jabo's video plugin from project64, it is the best near enough, (reason its not in 1964 is because its a part of project64 so thats why the manual installation is needed.)