Hi Scott
Netfabb studio is free and is all I use, it is also quite simple.
This is my workflow [might help you get your head round things]
1 - I Draw the model in Sketchup full size [i.e. 1:1 scale]
reasons - sketchup will not draw circles smaller than 0.44mm radius. The smallest dimension FUD will print is 0.1mm so when drawing think the smallest dimension that I can draw is 16mm [i.e. 16 divided by 160 = 0.1].
2 "save a copy as " often, so if you make a catastrophic mistake it is easy to go back and restart.
3 Check the mesh regularly in netfabb, I take the opinion that if netfabb finds a fault I would rather correct it than let the programme correct it as the programme might fix it a way I am not happy with. Checking regularly means you are not trying to fix a lot of problems at the end.
4 When the model is complete, check it in nefabb, if all ok rescale it in netfabb [netfabb will do as it is told and scale down below the 0.44mm radius that sketchup will draw] and export it as a new stl file. Upload to Shapeways.
Hope all that makes sense.
As Husker has said there is a couple of flaws, [hey, I made them to and still do] so you will get an email from shapeways saying the model will not print, when you upload they only do an automated initial printable check which looks at overall dimensions, when they prepare the machines print run an actual person runs the model through netfabb which will throw up any faults.
As I said, like Husker only started just over a year ago and it can be frustrating at times, the end result is really satisfying. There is always help out there in cyberspace when you get a problem.
Alexander
