This thread is for ACE for ArmA1 - you want the ArmA2 thread.
But to answer your question. ACE supports multiple action modes.
Vanilla has just the weapons select ( 'F' ) and action menu ( middle mouse button ).
ACE adds interaction with self ( apps button ) and interaction with others ( right windows button ).
Deploying mines is via the self-interaction menu. Some you need to aim, all need arming.
Recommend reading up on this stuff - either at the official ACE wagn system http://ace.dev-heaven.net/Home
or the FreeACE wiki http://freeace.wikkii.com/wiki/Main_Page