I believe the correct format for the shortcut command line is "+set sv_pure 0."
It sounds like it's loading the FritzA.campaign, which is included in Fritz0.pk3. I don't know why -- it's never happened to me so I haven't yet had to debug such a situation.
All I can suggest is to delete all the *.campaign files from Fritz0.pk3 and try again. Use your zip program to open Fritz0.pk3, look in the "scripts" folder and you'll see six campaigns there along with some other files. Remove those campaigns and see if that fixes your problem.
