My understanding is that some entities reflect light differently if they are dynamic.I don't have a techincal explaination but I have found through countless hours of working with FPSC that when you change a dynamic entity to static it can do that.It works the other way as well.Sometimes in test/game you will see a static entity that looks like rough and change it to dynamic and it looks great.
As long as you set isimmobile to 1 in the .fpe file or to yes if you are adjusting it in editor and give the entity no main or disappear script whether it is dynamic or not should not affect the performance of your game.
Keep in mind this is a "touch and go" kind of thing and sometimes switching an entity from static to dynamic or vice versa can have some weird effects.
I won't even get into what happens when you start mixing static and dynamic lighting.
This is also the reason that some of the entities from the model packs are dynamic when they could have been static.
Please have mercy and use the search function.
