STL file: http://www.geekhaus.com/makerhome/day8_legomarble.stl
Tinkercad link: https://tinkercad.com/things/31fZLaKI5PM-day-8-lego-marble-run-chapter-2
Thingiverse link: http://www.thingiverse.com/thing:145842
Settings: MakerWare "low" with no raft and custom supports as described below, with two pieces printing in 37 minutes.
Technical notes: To make the supports easier to remove, with enough support to hold up the ramps but no support inside the "LEGO" part, I made a new slicing profile based on the "MakerBot Slicer Low PLA Template" where I changed the lines that initially appear as:
"bridgeAnchorMinimumLength": 0.8,
"bridgeAnchorWidth": 0.8,
"raftBaseDensity": 0.7,
"doSupport": false,
"supportDensity": 0.2,
"supportExtraDistance": 0.5,
"supportAngle": 68.0,
to each of the following, respectively:
"bridgeAnchorMinimumLength": 0.3,Still to come: More types of pieces - curves and corners, holes and spirals... ??
"bridgeAnchorWidth": 0.3,
"raftBaseDensity": 0.4,
"doSupport": true,
"supportDensity": 0.15,
"supportExtraDistance": 0,
"supportAngle": 80.0,