1) Jump across various clusters; J3 is best, but there is a J2 route as well as clusters where J1 works fine. If a large amount of J1 ships want to transfer between clusters, there are J1 carriers. But ships like Mark Lucas' Boudicca Frontier Trader, which is J2/3 with collapsible tanks in it's cargo hold.
2) Yes, I have a definite background, which I will put back together again as I had it in a wiki on Obsidian Portal, which when they changed software it crashed.
Basically, it is 1323, 75 years after the events of 1248, all OTU history (Golden Age, Rebellion, Virus, etc.) remains intact. Most of the worlds were settled by refugees in the 1120's and 1130's on; the big worlds, those with high populations and A or B class starports are the best real estate, big garden type worlds, with only recently people beginning to expand out into the other systems. There are different groups though, minor aliens, Zhodani, Vlazhdumecta, Solomani such as from the Regency of Muirimi, "Scruffians" (Hunter S Thompsen's "Linkhorns"), even a few Vargr and Aslan kicking around. It is a kitchen sink type setting, very frontier, a big mix of populations, and different ideas for adventures, such as in the Ulfberht subsector, where the are both Sword Worlders and a Transhumanist world ala various influences for example. I do have a fair amount of worlds detailed, with various adventure hooks; such as what were the Scouts doing out here on their own before re-contact with the Imperium, have they developed independently, can they still be trusted?
2) It is on the edge of charted space, I have six sectors stated out so far: Fulani, Astron, Theron, Theta Borealis, Chiep Zhez, and Mavuzog:
Though none with all the subsectors turned into pdf's like Astron.