Earlier quoted context omitted.
The one that's been getting me lately is the split between Xcode 7/Swift 2.2 and 8/3. We have an older project in Swift 2 (yes, it's slated to get changed over, just not yet), and new work on a project in 3. If I try to open one while the other is already open, one of the Xcodes invariably freezes or crashes. I will say, though, that I've always liked IB (though not storyboards). But then there's the wonderful "Oh, y…
Can you still submit apps with Xcode 7? In response to your problem, having done the Xcode Old/Xcode New dance every year since 2012, I got into the habit of making sure they are never running concurrently. Things get even worse if you run xcodebuild on the command line while a different UI version is running.
As for other problems, please file radars and respond to requests for additional information. I have been on the external side of radar, I know it can be frustrating, but we do read them and we do take direct action based on them. Even duplicates are very useful.