Hi Reece,
I just tested Cepstral SwiftTalker with latest git (see bug: http://bugs.winehq.org/show_bug.cgi?id=12534) and I can't see the options from the `control` program. You might want to get this and other applets displaying/working before creating default Wine-specific ones (e.g. like the one installed by Internet Explorer).
I'll look into that, then. I know that the shell namespace control panel does check the registry for entries (could you try using a program like the ReactOS Explorer to browse the control panel and see if it shows up there?), but I'm not sure if the standalone control.exe does. Ideally, the standalone control.exe would be replaced with a stub that launches the Explorer, but of course Wine doesn't have a built-in Explorer yet.
I'll do some testing with this app later and see what the problem is.
Cheers,