Just wanted to check how these two work.

Can they only be used separately or do they interact.

Eg: no bombs were dropped/launched in the system phase.

Would I then be able to use genius to drop a bomb but also trajectory simulator to launch using the 5 forward template after I move?

Short answer: no.

Longer answer: I can't think of a situation where they work together.

Trajectory Simulator specifies that it only works in the system phase.

But Genius' trigger is fully executing a maneuver.

So if you have some way to execute a maneuver in the System phase (none currently exists, none seems likely to exist), I suppose you could launch with Genius, but it seems highly unlikely. There have been various abilities in 1e which counted as "executing maneuvers" but other than SLAM (which can only be performed as a ship's normal action in the Perform Action step), I can't think of any off the top of my head.

Thanks.

We were playing a game at the weekend and we agreed it didn't seem right but I guess we were too tired to work out why. That makes it nice and clear.