I've run Adguard for Windows with Avast Free off and on for years and never experienced a BSOD.. maybe I've just been lucky. I tend to use the Adguard extension now anyway as less delays when opening multiple tabs.
Seems likely that the issue with AdGuard for Windows crashes were probably caused by a setting in 'Do Not Spy' 'Disable background applications'. And after I unchecked it AdGuard 'seems' OK - I shouldn't have enabled it in the first place (of course time will tell)