One interesting history I read for BSG stated that the Cylons actually served on the early battlestars before the cylon rebellion as soldiers and space labor. It wasn't until the rebellion that they yanked all the wireless tech so that the cylons couldnt access it. Galactica's class of ship was one of the first that had an all human crew according to this history. I think we will see a lot more of this when Blood and Chrome comes out.

Any way here is my take on it. Just like us, we make this huge leap in space flight with the Nasa programs and we are still driving around internal combustion engine auto's. Are computer tech takes some serious turns in advancement and miniturization and our space program becomes obsolete. I think that technology goes in cycles. I think one of the reasons (besides its earth tv) that you saw Hummer like jeeps and regular heavy trucks in the show is that they worked so their industrial complex didnt spend anymore time trying to reinvent the wheel. They discovered FTL flight so now they were focusing on interstellar travel and not so much on what they were putting out on the roads. After all if interstellar travel were the big thing a lot more industry would boom to service that instead of some old clunky cars. I'm sure in their world the cars probably ran on more efficient engines than gas burners like electric, chemical, or helium 3 power cells. The development of Gauss tech is expected since we are almost there ourselves. One article I read about the new Galactica is that the STL drives are Ion Plasma Based with Fusion power plants. The same article said that galactica's engines were not particuarly fast bc of its size and the engines design but they weren't needed to be fast because the ship had FTL. Most of the weapons seen on the new BSG were described as some kind of gauss, coil gun, or rail gun tech. I think that i read that their pistols were Binary proellent caseless rounds. Two separately inert chemicals which are hamless separate but reactive when mixed.

I don't think it would be necessary to have a gauss launcher as a space crafts intertia could be used to assist in launch and since there is no gravity there is no escape velocity that needs to be satisfied unless the ship is massive enough to create its own gravity or has some kind of artificial gravity field generator that effects the launch bay too.