In the GFL Mod they are using Klingon photons for some reason and they can't be set to proximity. But the quantum torps can.
Group them under a hot key of your choice (1,2,3etc,) Then look to the right of the panel that says Quantum Torps, and you will see the proximity switch.
If you are gunning for bases on the GFL mod, make sure you have a BB and a Legendary crew or it will take you out easy.
Stay just out of range until your torps are charged then go in using evasive maneuvers. Then when you just get in range hit steady as she goes, and fire. Turn and get out of range of the disrupter,phaser 5s as fast as possible or they will tear you apart.
Only go in for the kill after you have starcastled the defence platforms to nothing then get out of range of the base.
Repeat the same tactics for the base.
It takes a while and you need some skill. The defence platforms and bases are truly formidable now.
And a great deal of fun to hunt.
QaP ` LaH!!