I think the Vassal module sticks too closely to the board game, leaving large paperwork overheads that could be handled on-board. If the VASSAL module designer reads this I suggest:
• Place teams under their ship counters.
• Give teams full range of strengths on-counter like the German STs so they can just be rotated through, and ammo counts likewise
• Give ships on-counter crew/passenger counts
• Give ships on-counter gun/torp strengths
• Give Campbeltown third side showing scuttled.