Lol well this is already something Blockland is yet to be seen, Now you want me to try and add the OMS burners? Lol, Cant do numpads for most people thats the keys for Moving bricks around, And as I said sir all the keys will be bindable by the player himself/herself so itd be their choice on the keys, I finished the Fuel Tank but it did not save for some reason so now Im dreading starting over :) But will do it.
Edit: Would you like it to have fuel as well? Wish I could make a script add on to refuel it lol You could make an ISS then onVehicletouch> Vehicle> AddFuel, I can make it have fuel I believe just dont know about refueling, Then again youd only need fuel to get up there and then you know how they land so I wont explain that here.