its the last ship on the right on the bottom row, i completed all the missions tho...i think
That last ship is unlocked when you get 130 gold bricks.
That's helpful, don't you NEED a Separatist tank to unlock Separatist Assault (if not then how do you?)
To unlock the Separatist assault you just need to access the console in the vehicle hangar on the Invisible Hand one time. The vehicles themselves you'll unlock once you build them once in any mission. For the Separatist vehicles I think you can only do this in the assault missions.
the console in the vehicle hanger is behind a "Tank Silver" wall (I don't know what else to call the silver walls that explosives can't break through, they should have chosen a different colour metal for them)
meaning you need at least one tank to be able to do the Separatist Assault
True, but the tank you can use is the Pirate Speeder, which you unlock in an early Dooku mission. You don't need a Separatist tank to do it. I don't think it's possible to have a Separatist tank before you blow up that wall, is it? Maybe I had Super Speeders before I did it? I didn't think that was the case though.