I've been making a game with Xcode 6 GM using SpriteKit, and for some reason out of the blue a number of my .SKS particle files are now crashing Xcode which makes them impossible to open. I've also noticed that the files that are crashing Xcode are also crashing my App when unachieved using the NSKeyedUnarchiver. So I'm assuming that given the circumstances of the crashes, some of my SKS files have become corrupt. Is there any resolution to this other than starting from scratch all over again for all of my corrupt SKS particle files? Can I somehow manually modify the SKS files through an external editor and fix the issue? Also are there any steps I can take in the future to ensure my SKS files don't become corrupted again (i.e. is there some bug in Xcode 6 that I should be aware of that's causing corrupted SKS files).
Edit: It appears Xcode is treating these files as Scenes rather than particle files which is leading to the crashes. So for some reason the Xcode 6 GM Sprite Kit Editor is not preserving file format correctly which is leading to particle files being saved as scene files resulting in a corrupted file.