saved game file vanishes

[RedDevil]

Anyone have an Idea?
Not on my PC or game, but I have a fellow helping me build a scenario for him.
He says his saved game file disappears when I send him an updated map file and he has to start all over again,  instead of being able to load his save file and continue finding map defects for me.

He unzips map file to folder and saved game file deletes?
 Never had issue with map file changes in game when testing, unless it was a pbem set up or hotseat perhaps?..

 I am able to start  scenario, play, save file, go edit map, save map, load game and continue on... but he cannot?
 I start standard game, human players both sides,  normal rules and just play both sides.

Dev