Oh ok. Well I guess I am going to have to just delete all my save states from version 0.142u2 since they probably can't carry over to version 0.144.
Maybe one day the save state feature will be greatly improved. I know it's probably not a top priority of the MAME devs since it has nothing to do with the MAME goal/purpose, but it would be really awesome if and when that feature ever gets improved.