Hi Kpt. Lehmann,
No problem, I like GW very much

and I can modifie the campaign RND file my self. Just to add this at the end of convoys you would like to be uboat reporting convoys or to be attacked by wolfpack, getting the group unit number right. You need Sergbuto's wolfpack mod.
[RndGroup x.RndUnit x]
Name=Type VIIA#1
Class=SSTypeVIIA
Type=200
Origin=German
Side=2
Commander=0
CargoExt=-1
CargoInt=-1
CfgDate=19390101
No=2
Escort=false
SpawnProbability=100
CrewRating=4
Mikael