I know this thread is old, but I ran into the same problem.
One partial solution is to use the SendKeys.Send function to simulate a second press of the alt key. For example, to simulate a user by pressing "alt-0":
sendkeys.send( "% 0" )
, Alt , .
, , Alt-. , , , Alt, .
Alt menustrip.activate, , - menustrip.deactivate Alt, , ...