Here's some things I had to figure out myself, that I wish Makerbot gave more instructions on for noobs like you and I.
In ReplicatorG, go to the GCode menu and select 'Edit Base Profiles'. You'll get a list of the default profiles that you can print with. Select the profile that fits your machine & setup and select 'Edit". A new window will pop up called Python. This is where you can change all your Skeinforge settings. Before you touch ANYTHING, go to:
www.example.com www.fabmetheus.crsndoo.com/wiki/index.php/Skeinforge
and familiarize yourself with what all the various parameters are. I also recommend making duplicates of the existing profiles and re-naming them before you change anything, so you don't screw up the defaults. By and large, the default profiles work pretty good.
When you generate GCode, and the print-o-matic window pops up you have to select which profile you want to use to slice your object. I have about three different profiles depending on the piece I'm printing. Rafted, Raftless, Large Piece, etc. It takes a day or so of tinkering to get it dialed in.
Read "How to Print Raftlessly'
www.wiki.makerbot.com/thingomatic-doc:raftless
and setup a new profile with those parameters. The instructions are a bit dated for the new versions of RepG though, now you set your Z home offset in 'Toolhead Onboard Preferences' in the "Machine" menu in RepG. You don't need to alter the GCode.
Personally, I was keen to get things setup so I could print raftlessly, but I still prefer the raft. By tweaking your z home offest you can get the raft so it peels off the part like velcro, but when you print without a raft the first few layers get smooshed and fat. It's ok if it's a flat object that you can cut or clean those few layers off easily after it's printed, but a complex part requires lots of cleanup. I'd rather peel off the raft and give a couple swipes on a sheet of 150 grit sandpaper. Done!
Also, if you haven't yet, replace the ABP with the aluminum build surface. It's well worth it.
Speaking as a relative new guy, it's frustrating how much old information there is on the Makerbot Wiki, and how unorganized and ambiguous the forum is.
Good Luck!
