Play in Editor Not Working Correctly

So here’s the story: I’ve been working on a project for sometime now in Unreal 4.7.6, and about halfway through, some problems regarding the play/simulate buttons began to occur. When I first open the project and hit play for the first time, it takes very long to actually play! (Sometimes up to 3 minutes!) But after that, it plays regularly. To make matters worse, when I updated the project to UE4.12.5, (on a different computer, mind you) it won’t play at all! Has anyone had any similar experience or know of a fix? I still have the old 10.7 project as well as the new one. Any advice would be well received. Thanks!

When it “won’t play at all” or “takes a long time to play,” what is printed to the output window at the time?

Also, how much RAM do you have in your machine?

I have 12 gigabytes of ram on my computer that it took forever to play on and 16 gigabytes of ram on the computer that it wouldn’t play at all on. This is hardly an issue anymore on my one with 16 gigabytes because I just installed Unreal Engine 4.7 and the very long time isn’t nearly as long. As for the output window, well It gives a lot of things once the level has started, but displays nothing during the 3 minutes it’s loading. Anything I should look for in there specifically, or do you want me to just post the whole log here?