Bugs in SCT

Ok, first Gumball :
One thing I'll say is: You should not post any issues here, as unknowledgeable or blatantly ignorant people will reply with either incorrect or useless answers here. (Definitely not calling out anyone here, would never do that.) If you are experiencing any issues, I'd recommend you post them on the Github page here: github.com/WinClassic/SimpleClassicTheme/issues
As to your issues:
This sounds like SCT is having trouble with loading SCTT, RetroBar or with killing explorer. I'd need to know what configuration you use to identify the problem better.
This is not a bug, rather a design flaw. SCTT was designed to be launched and managed by SCT. You cannot manually open SimpleClassicThemeTaskbar.exe, you have to select SCTT in the options menu of SCT, and then Enable SCT to enable Classic Theme and launch SCTT automatically. Unfortunately SCTT is not under development anymore, so this feature will not go away.
plusdeluxe :
With ExplorerPatcher it's a whole different issue. This is just a bad line of code within SCT 1.6, which will be fixed when 1.7 releases. SCT tries to let ExplorerPatcher restart explorer (in order to properly shut it down) but ExplorerPatcher's restart command doesn't always start explorer back up. SCT 1.7 will restart ExplorerPatcher, fixing this bug.
The first part (issues with Open-Shell) is incorrect, RetroBar should work fine with it. The second part is something that has bothered me for very long. RetroBars code to change the working area is terrible, it hides the normal taskbar by setting auto-hide on. Then it tries to set a new work area by registering itself as a toolbar and then it displays itself where the normal taskbar would go. SCTT does this way better: it fully hides Shell_TrayWnd, making it inactive. It then forces the new working area onto the system, and then it displays itself just outside the new working area. It doesn't inform any apps that the working area is changed, but that resolves the conflict of multiple apps trying to change the working area. I still don't know why RetroBar uses the first method to this day.
Lastly, anixx:
Firstly, SCT just is more advanced and offers more functionality. Secondly, your method involves creating sketchy batch scripts which some people just don't want: they just want a simple program like SCT. Lastly, no one here asked about that method. You keep mentioning your Classic Theme method forcibly everywhere on the forum and it sickens me. You're only confusing people more with everything you post: if someone has a broken setup, they aren't helped by using another sketchy method which will break stuff even more when used in conjunction with what they already have. And I can't state it enough: no one asked, so there's no reason to mention it here.

There's indeed no bath scripts, but there is like 7 tasks which is basically a batch script in disguise. My main point is that it's completely incompatible with SCT. SCT doesn't support this taskbar at all (only in some unreleased alpha builds) and will not support it in the future. My vision for SCT is replacing the bad functionality within Windows, not patching Windows to look good but with a million bugs. Redirecting users to your own Classic Theme method on a thread asking for help with the taskbars provides by SCT is, in my eyes, unnecessary. 
Explorer not starting is a bug within SCT (actually with ExplorerPatcher, but that aside), that has nothing to do with your Classic Theme method at all. Using RetroBar was just a slight derailment from the thread, but is still relevant as we're talking about SCT here, not Classic Theme in general. I really don't mind if you suggest new users to use your Classic Theme method, in fact, I encourage it. But don't go on all threads even slightly Classic Theme related to brag about your tutorial and how it's better than everything else.