Looks like I was able to play around with your Aegis Reloaded campaign file and get the mechs and pilots readied for the mission.
I suspect that since the campaign file is in 47.4 now, we might as well use that.
Here are the 5 pilots, deployed to the Ceres metal factory mission:
With the 5 mechs deployed to the Attack on Ceres Metals, you should see this in the briefing room:
If the mission is completely generated... then you could click the Start Game Button.
If the mission is not completely generated in MekHQ, then you can also just Click the Export Mul file button, and MekHQ will export a mul file for use in Megamek. Once the battle is fought, I can then explain how to import the results back into MekHQ.
Lastly, here is the Campaign file for these 5 mechs and pilots of Aegis Division just before attacking the Ceres Metal factory.