I had nearly ALL these same issues listed … haha
I ended up having to remake everything because it literally broke all my maps and blueprints … well … it broke everything …
Deleted 100% of my devkit files so that i can fresh install and start over (i had to start over anyways, since, it was all broken now)
This is the process that lead to breaking everything:
Install everything as instructed a few weeks ago
Everything works (for the most part) and all my stuff loads quickly
See there is an update
Download both parts for the update (github and that google docs RAR)
unpack it all as per instructions
load program > everything broken
load “TheIsland_Small” > like 300 errors and broken objects
oh, add in that suddenly it wont recognize ANY of my maps primary map files (example: sees all the parts of “TheIsland” but wont let me open “TheIsland” primary umap file after validating and “fixing” the issues via steam)
Whats done is done, re-downloading the entire thing via the Unreal Launcher and Steam … now i shake my first at the slow download speeds im getting … lulz.