Another thing I thought was there that you might not have gotten around to yet. I thought you had introduced a non-TNT engine tech, so a pre-TNT race could have REALLY SLOW survey ships. Not a big deal if you haven't done it - I'll have engines researched soon, EXCEPT:
Soon after I researched TNT, those pesky civilians decided to build a space center. I haven't seen any problems yet, but I'm a little concerned that I might hit a bug when they try to build a civilian cargo or survey ship and discover that these are impossible due to a lack of the appropriate design. I had already hit "new" on the Class Design (F5) screen which created a hull with no engines, so I added an ICBM control system to make it a non-civilian design (so those pesky civilians wouldn't try to build on).
John