I goofed with Fleet Command and 688i some more. 688i works in Win7 with compatibility set to "Windows 95". Fleet Command works with compatibility set to "Windows 98 SE/Win2000". In Fleet Command, the slowdown can be remedied by placing the mouse over the lower left map and hitting CTRL-V, which refreshes the graphics. The trick for Sub Command works just like DW.
Sink 'em all!