Xcode 6.1 is working on Mavericks code completion

I tried deleting my derived data and restarting Xcode and it works for a few seconds until indexing is complete and then breaks again.

Does anyone have any recommendations on how to fix this?

I have searched on Apple developer forums and there are many other users having the same problem. They say to revert to a previous version of Xcode 6, but I don't know where to find it, so any advice on this would be much appreciated as well.

I never really understood how much I rely on Code Completion, I get pretty stuck until I get this fix.

PLEASE, HELP!