In v.12 on my PC, i am having intermittent issues with layouts that have been created not saving. All of the plan information is there when i re-open the file (even items placed after the layouts were made), but any new layouts and masters are gone. This has happened with both PLNs and PLPs. I have several other files in v12 that do not have this issue. Any clue as to why ArchiCAD would selectively not save layouts when closing? No crashes or errors appear when exiting the program.