For explanation:
This bug seems to happen when you play with Warfare Skill enabled and click somewhere in Hero screen. I added a check that the script only runs when clicking on secondary skill text fields.
Next fix:
In the file 7 wog - enhanced artifacts.erm the line erm line 344 was messed up. While I could not get the error message you showed, the line was faulty non the less and the increased spell damage from the artifacts would not work for the defender.
The correct line must be: