UE4 When Previewing A Game

So whenever I start up my game inside of UE4 it seems to crash, not really crash but freezes I should say, so I wait awhile for it to respond again, but nothing happens so I have to completely restart the engine, and it happens all over again, any solutions?

What does your level look like? If your world has too many actors or is full of foliage that can take a serious toll on your system and it may take a while for your level to load. Can your GPU handle the world?
Are you able to exit your play preview? or does your whole computer freeze? For an issue like this, there could be many possibilities of why it’s freezing.

Yeah now that I think about it I did add many lights and many actors, perhaps that’s what’s causing the problem.

If you really need certain lights, but it’s costing too much, performance wise, try setting the lights to static or stationary instead of dynamic.

If you have actors like projectiles, can they be destroyed after they’ve served their purpose?

Also, look at your engine scalability settings. I think by default, the engine sets them to “Epic” quality and the material quality at high. That could be too much or just right so it all depends on your system and what other apps you’re running at the same time.