Sorry for posting again, but the thread I posted in seems dead?

For some reason I don't seem to be able to do this.
OK. So, let me be very precise here:
I have 2 menus:
[1] title = Main Menu,  Type = mainmenu, #modules = 3, ID=1
[2] title = Main Menu Registered, Type = mainmenureg, #modules = 1, ID = 7

Now I have 2 modules of type mod_mainmenu, both in menu position, and pages = none
[1] title = Main Menu, enabled = false, ID = 1, menu name = mainmenu
[2] title = Main Menu Registered, enabled = false, ID = 78, menu name = mainmenureg

Finally I have a Metamod module:
[1] title = MetaMod Main, position = menu, enabled = false, ID = 79, show_title = NO

And in the PHP box

if (MM_LOGGED_IN) return 78;
else return 1;

What am I doing wrong?
Your comments are certainly very welcome!
Thanx,
Lolke