Supporters who opt for the $99 reward may choose the operating system (currently Windows or Mac). You don't need to do anything at the time of your pledge. We will send out a survey when the Kickstarter closes and you may choose then.
A: Yes. You can fix, scale, or re-orient the part and then export it as an .stl
A: Yes we can provide a Linux version at some point. We are writing our code in QT cross-platform environment and can easily compile a Linux version. We are considering adding an offering.
A: Not at this time. We will be adding export to .slc format to version 1.0 (October 2012) of our software.
Don't see the answer to your question? Ask the project creator directly.