I was able to create a brand new 4.2 project, insert a combination of blueprints, and cause the crash reliably. The crash only seems to occur when all of the attached blueprints are in the project - if any one of them is missing, no crash. Just copy the attached folder into the Content of a new project, start it, and try to open the blueprint BP_PlayerCharacter. You should get the crash then.
The blueprints all have references to each other and three of them form a BP hierarchy, so it’s very difficult to narrow down further what the problem is here.