If AnyMeeting was installed "manually" (likely by copying the appropriate files to the correct locations, and registering any .dll files needed), then it probably doesn't show as installed since the registry entries needed for it to show as installed were probably not created. The AnyMeeting tech should add those registry entries when installing it manually. Missing registry entries would also account for the missing functionality as well.

If you could get AnyMeeting installed properly onto one computer, you could search for the registry entries that are created, export them, and import them onto a non-working or partially working system.

Did you get the differeing version for different users issue resolved?