What choices to I have for different looking ships? My aliens are not part of any existing faction, so I don't want them to look like they are using klingon or gorn or romulan ships.
Some of the Orion and Gorn stuff is fairly generic, but all of it's used in game, and potentially familiar therefore to players. Using a skin from a lower-level enemy like that on a higher-level enemy ship is the best tactic for creating generic ships. NPC ships don't have any customization like player ships, either. They're lower rez models, since you see them at a distance.
I suppose it could be done through a Beta 5 interface cube. Can I create a multi-colored cube?
You can't really create assets, only use the ones in the game. There's no central listing of all of them; nobody's been willing to put in the man-years necessary to create wiki pages for them all, there are thousands.
If you use a generic computer console and have players speak to something identifying itself as a Beta 5, they will accept it; but you will not be able to make it look like one.
Gary Seven may have been the only agent of his organization on Earth in 1969; perhaps in 1973 he isn't. Or perhaps Gary wasn't in the "need to know" loop for this operation. Or perhaps he recruited some local agents, who are interacting with you in his stead?
Foundry access only costs 10k Dil; that's less than two days worth, you can earn it pretty quickly.