I'm waiting to get this in TPB, so I haven't read it. And I can't really comment that much on it, but in regard to your comments about communications construction and communications repair, first off, shouldn't it be engineering instead of construction? Second, I went to the Wookiepedia, and I saw what it looked like. Having seen it, I think it would be better to use equipment engineering. Tied in to that, according to the Star Wars RPG Sourcebook REUP that's created by The Rancor Pit, equipment engineering is an advanced skill that requires 5D in equipment repair.

"Officially" it seems to vary depending on what you're building, as both of the below are mentioned in published materials.
Repulsorlift Construction, Droid Construction
Walker Engineering, Repulsorlift Engineering

Yes, Repulsorlift features as both, so I guess they couldn't decide either.

And yes you're right, the Engineering/Construction skills are Advanced Skills.

Oh, and just found on the master skills list, that Communications Repair is mentioned in an official supplement.

Then perhaps you should have engineering and construction. It seems like a natural progression. IMO, you need to know how to repair something before you can learn to design/engineer something. And you need to know how to repair and design/engineer something before learning to construct something. Repair -> Engineering -> Construction.