Done in v4.5.6.2 beta: if the file "7+ Taskbar Tweaker.ico" exists, it's used as a tray icon instead of the original one.

Why do you think that 7TT causes the issue?
Did you try to use your PC with the tweaker turned off? Does it fix the issue?
In general, from your description it sounds like Dexpot is the app to blame here, as it handles the virtual desktop switching.

That's a good idea, thanks. I'll look at it.

You can change the icon manually by using a resource editor, such as Resource Hacker.
The drawback of this approach is that the icon will be restored upon the next update.

Currently, I don't plan to introduce an option to choose the tray icon color, but let's keep this topic open and see whether there's more feedback about it.

I'm going to try your win7appid suggestion :D

I think that's the best solution for you. Try it and let me know whether it worked.

You can access the Advanced Options from the main window context menu.

Done in 7+ Taskbar Twekaer v4.5.6.

Should be fixed in 7+ Taskbar Twekaer v4.5.6.

7+ Taskbar Twekaer v4.5.6 was just released. It should fix the issue.

It already works.
If there's a specific option which doesn't work for you, please be more specific.
If you're using an alternative implementation, e.g. UltraMon or DisplayFusion, the tweaker won't work for it.