This issue is not a problem with Adobe Connect. Windows does not allow remote control of Task Manager.
In Windows 8 machine, if you are sharing your screen and have given access control to the user and a metro application such as task Manager comes over the screen being shared, then the user who is controlling the screen will not be able to control any more.
Host will be able to accept the request control but user will not be able to control the screen.
User should be able to control the screen.