Hi Weinstube
Ensure that the Ships and Escorts have waypoints and that the ships and Uboats have the same entry time and date as the Mission start date and time else it wont run.
You could try this open up one of the LSH3 Single player Missions in the Mission Editor compare how that mission is set up Date time
of Mission same as ships and Uboats same mission name in mission Briefing and same Mission mis File name and Same Folder Name
then see whats missing from your Mission or what needs a little tweak
Please let me know how you get on i would like to help you get squared away Weinstube ive had a bit of experience writing SH3 Single/Multiplayer Missions and Campaigns
