If I upgrade from gwm200 to 202 on nw65sp6, questions :

1. any way to roll back on server ?
2. after upgrade to 202, any way to stop (not prompt) for gwm client
update ?
I want to control by zen, who wants to update to 202 client.
3. gwm200 client works fine on gwm202 server ?

any advise would be appreciated.