Having the same issue. Sorta.
Loaded ClassicShell 4.2.4 and everything worked fine, until the last Windows update. Now, ClassicShell does not open by default when I restart my PC, I have to go into the menus and start it by clicking on its icon. THEN, it runs fine and opens when I click the Start button. Until the next restart.
My setting are set so that it runs on Windows Start, and it is set to be the default for left-click and Windows button.
I tried uninstalling and re-installing. Did not resolve the issue.

In addition, probably not a ClassicShell issue.. since installing ClassicShell, new programs installed on my PC do NOT show up anywhere in the native Windows 10 menu. So, all those programs are lost on my PC unless I use the ClassicShell > Programs menu.
