- Uninstall the mission.

- Open both zips in a file manager like Total Commander.

- Copy and let it overwrite the old files in the mission zip with the new ones it asks to. Make sure you don’t unzip it to a subfolder within the mission root!

- Rename the mission zip from ...v1.x to ...v1.2.

- Reinstall and play.

note: the earlier saves for this mission will not work after updating!