I just ran a quick test, creating a M&K object in layout 1, marking it global, and making several new layouts and extra event sheets, and it shows up in all of them. So I don't know what's going on.
What version are you running?
If I create a new direct x game, create a M&K object in layout 1 and set it to global and create a new layout, the M&K still will only show up in layout 1 and not in layout 2.
I'll put it into the bug tracker.