Hello,
I just started using UE4 and also could not get the Xcode auto completion working on some of my projects. I am currently using UE 4.4.3 (the source code version) and Xcode 6.0.1. The problem seems to be related to spaces in path to the Engine source code. I initially had the Engine code under “Unreal Projects” and auto completion did not work at all on any projects created using UE under “Unreal Projects”. I move the code to “/Users/Shared/UnrealSource”, recompiled and now autocompletion is working fine (after indexing is completed). Looking at the project settings I can see that there are still some paths with spaces which are not correctly interpreted by Xcode.
Maybe there are other new users of UE4 with a similar problem.
