Gmod Freeze Help - Mac

Hi, I’ve just got GMod for my iMac and I’m having problems with right clicking to freeze props and ragdolls. Basically, it won’t let me do it unless I press F3 twice to minimize the game then bring it back up and then it works, but as you can imagine this is a real pain in the arse. Anyone help me with this problem?

And just another quick question, I don’t actually have a numerica keypad for my keyboard, is there a way I can change the settings of the right side of the menu i.e. the toolbox options to some of keys? Or should I just buy a cheap USB keyboard to use for the game?

Cheers, John.