I am just startitg to sniff informations about Leningrad (thus I allready got somethig), so for Vlasov again shortly:
There were lots of Russians in german army, not only Vlasovs two divisions. Too many of Russians (not only Russians, all nations of USSR, Germans called them Hiwis or such as?), that, in fact, the Wehrmacht could not work without them.
Shooting to own people is indeed bad, but maybe he considers himself as a kind of rebel against Stalin and komunist party? Btw., his army did not fight much against Russians, only once in regular battle (as I remember, maybe more times).
Uprising in Prague is quite an interesting for me, as it is only about 100 km (1 hour by train) to get there. And if there were not those Vlasov forces there just in right time, many of ancient buildings and other sights were gone...
Btw., Vlasov himself did not want to fight Germans, one of his officers gave order to help to Prague.