i have only used the program since this moring.
When I change channels the program seems to continue downloading
from the previous channel. This would clog uo the mainframe.
Is there some way I can be sure that I have logged out of the old channel when I go to the new one?

ProgDVB close channel before open new (some time spend 1-3 second for that). But may be WM SDK not close. How you detect that?

PS: Try install last WMP.