A question about slic3r.

Slic3r is not as tolerant to corrupt STL files as other gcode compilers.  I have seen weird results as well.  Do you see any errror messages in the log pane during Slicing?  How do you generate the STL?    With Solidworks, sometimes it asks if I want to output all bodies or just selected bodies when I save as an STL even though there is only one object.  If I select all bodies then I often get bad geometries which confused Slic3R (but not Skeinforge).  Also some of the STL file's I've downloaded cause problems because the surface normal vectors point in instead of out on parts of the model.  Slic3r can't handle this either.  To get those to print, I had to load them with Meshlab, select the offending sections and run the invert vector tool.  Meshlab is a good tool to have in general as it also fixes other STL problems like duplicate vertices, etc.