Do I have to activate them every time I want to use them or are they passive?

 

Can someone give me an explaination? Thanks.

For lighsaber forms: Once they're activated, they stay in effect as long as you're wielding a lightsaber. Sometimes however, area transitions annoyingly reset your form. So just check on the HUD to see which form you've currently activated.

 

Scripts (agressive, stationary, etc), work in a similar way.

The tendency of your attack modifier to become massively inflated, and the ability to mod your saber to an extreme degree make the choice of saber-forms kinda pointless. I never found them to make that much of a difference in gameplay. The force forms on the other hand at least had some pretty palpable effects, noticeable change in damage spread, better regen, etc.