I was trying to slice the WInterfell model http://www.thingiverse.com/thing:39680 and had Skeinforge tanking with some error in comb.
Google to the rescue. It turned out that there is a bug that will sometimes stop Skeinforge from processing small details.
For anyone that encounters the same problem, the fix can be found here
https://groups.google.com/forum/?fromgroups=#!msg/ultimaker/ughfwkGTSzE/GpB-QLFSb1cJ
Why not zoidberg slic3r?
I just can’t get as nice a print out of slic3r than i get out of skeinforge.