Does the issue occur in the editor or during gameplay?
If it's a gameplay issue, please specify which movement system and camera type you're using (free movement vs. grid movement, third-person vs. first-person) or N/A if not applicable:
Briefly describe the issue you're experiencing:
After using change_player to swap characters, if you stand still, and save game, it will save fine.
However, if you move off the tile you were standing on when you changed player, and then save, you will get a load of errors, and save doesn't occur.
Are there any errors in the in-game debug console or external console window?

Provide the steps necessary to reproduce the issue:
play a game with two characters in the project
add character 2 to party member roster
use change_player to swap to the second character
don't move afterwards...save game....works
5.walk around a bit as the new character
- try and save again....no save takes place..and errors in terminal instead.
Provide a download link to the bare bones project (strongly recommended if it's an in-game issue, since this helps significantly when attempting to reproduce it; the report will also be given more priority in this case):
May send a bare bones project later, but its pretty straight forward to reproduce.