Hi! I've just loaded a saved game where your mod was active but hadn't been used yet to switch characters. This resulted in a crash:

 355.129 Error AppManagerStates.cpp:1662: The mod Multiple Characters (0.3.4) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event multiple-characters::on_configuration_changed
__multiple-characters__/control.lua:358: attempt to index field 'character_tag' (a nil value)
stack traceback:
  __multiple-characters__/control.lua:358: in function 'unregister_character'
  __multiple-characters__/control.lua:373: in function <__multiple-characters__/control.lua:370>

Changing line 358 to

if global.character_tag and global.character_tag[character.unit_number] ~= nil then

will fix this. So far, I didn't get another crash yet, but line 364 also looks like it could break. Better make sure that a valid tag exists before trying to destroy it:

if tag and tag.valid then
  tag.destroy()
end

Same here. Thanks for fix hint, will change on my side and wait for update

Thanks for the reports! It should be fixed in 0.3.5

Yes, it's working now. Thanks for the quick fix! :-)