I'm still finding odd bugs with Classic Shell on windowsn 8.1 home prem x64.
One that is consistent is, in its default settings, accesses to folders in Windows Explorer have an unusual delay before the contents of the folder are apparent. I notice this particularly accessing the Downloads Folder when Windows Explorer is not already up/running.
Perhaps I should just turn off all features related to Windows Explorer? [I know of nothing I need CS to do there...]
I also have noticed some random event/s will defeat Classic Shell and I cannot track/correlate this with anything in the Windows Event log. Few times I've had it just "not be there" - not alive, and instead I will be looking at the default 8.1 desktop settings. After a reboot, CS will be coherent again.