Weird behavior,
Compiled 4.12, No errors. Try to run Infiltrator, works in editor (even if all the textures are low res, in viewport still not fixed. Streaming totaly screwed in editor in viewport run mode and been like that for at least the last 3-4 releases) but play stand alone game in editor just brings up a black window which is totally unresponsive, tried 5-6 times with deleting old version, new version from vault and rebuilt all shaders etc still the same thing.
Play stand alone was the only way i could preview scene’s with working textures but now that doesnt work either. Oh dear, maybe it’s the fact there was only 6 previews this time around 
Come on, don’t make me spend ages downloading dependency’s that cant be intelligently updated from one build to the next so only changed or removed deps need updating (which would make having to download 4 GB deps on a wifi connection not needed and far more simple for rebuilds, updates,) but to also have no working preview in editor window working correctly with textures, and now play standalone mode not working i have no way to see what im developing. I normally wouldn’t give epic **** like this but this RELEASE is useless.
FIX please, Maybe you need to go to 20 previews from now on
HAHAHA, Just to update after 22 mins, the stand alone window now has loaded infiltrator. Last build on same hardware took 1-2 mins to load. Now 22 mins. I dont call that progress