worstje, to fix number 2 on your Known Issues list, have a look at AppMutex in the fine Inno Setup helpfile. There's also the CheckForMutexes support function, might you want to check it from some Code.
And here is a way to create it in C# (for if you didn't know).
-Ath
Yeah I know of it. I already use OpenThreadWaitHandle or something along that name (Winapi: CreateEvent) for my single-instance functionality, but it doesn't appear as if Inno supports checking for such a thing... which is a rather annoying thing, I might say. I might have to add a mutex too, but then I'll have '3' things meant for single instance stuff: Mutex, CreateEvent and the COM IDropTarget local-server I use to handle the shell extension.
Just tested JottiQ 0.9.5 on Vista 32 bit.
Guess Vista doesn't like the shell extension, because it's not showing in the context menu of Explorer, or at least not for the files I tried it with. I'll do an uninstall/reinstall to see if I accidentally unchecked that option. [...] And that didn't help a bit, neither when checking the 'Explorer Integration affects All Users' option, so that might need a fix. Vista's UAC is turned off, btw.
This worked fine on 2 of my Win7 x64 setups, one with UAC in it's default setting and one with UAC turned off.
-Ath
Finally, a Vista user! I've been trying like crazy to have someone test on Vista.
I am surprised it does not work on Vista - it works on XP, it works on 7, you'd expect it to deal fine with the halfway point. Is it the 32-bit or 64-bit variety, or had you got the ability to try on both OSes?
If you run JottiQ and use the Settings window to enable/disable the shell extension, does it add a shield to the OK button? (Or when clicking OK ask for elevation for that matter.) If it does, you are using it for the entire machine. For now though, let's avoid any and all UAC issues and focus on the 'explorer integration affects all users' setting being turned OFF as it is by default. (If you simply extract the .7z archive, that is the 'mode' you end up using.)
Assuming you can't get the shell extension to activate through the Settings screen either, open up a dosbox, browse to the JottiQ directory, and type:
regsvr32.exe JQcm32.dll
(If you've got 64-bit, you'll want to do the same for the other dll file as well.) It will pop up that it succeeded, or it will throw an error in your face. If it does the latter, I'd be very interested in the error in question.
Also tested JottiQ 0.9.5 on WinXP 32 bit, but it has the same issue with the context menu as Vista 32 bit has, so it's most likely that that little bugger (the shellextension that is) doesn't behave as it should.
The advantage is that it doesn't want to reboot after a successful uninstall 
-Ath
The shell extension _should_ work on XP.
I've tested it to death myself. Can you explain what you did exactly? Maybe something else went wrong somehow.
I can't remember the exact namespace now, but I've easily implemented detection of all running processes in past projects - just a few lines of code. Must be easily found on search engines, or I wouldn't have been able to do it 
-kyrathaba
I'll look into it then; if it is as simple as you say it is worth digging into. Some things I expected to be simple as pie ended up taking full days though, so you can see why I am hesitant in committing to the idea.
