Free hands & full attacks

[ellbent]

Hey hey, folks. I recently purchased a handcannon in my Starfinder game, which doesn't allow a full attack (given it is unwieldy) unless my character has a free hand (as it the free hands (1) property).

I don't seem to have the option to enable full attacks for this weapon in the gear symbol that I do with other ranged weapons, and there's no tab to switch over to when making an attack roll. I also can't find anywhere in the weapon's edit/info screen to make that available -- a checkbox for 'using two hands' or anything like that.

Is there any way in Hero Lab for either me or my GM to make full attacks available for a weapon with unwieldy & free hands?