I think it is related to my Slicer (modified skeinforge by myriwell), because noone else reported such problems:
In every .gcode file ''all'' individual layer information are calculated ok (plausible values). But in Model Info most values are shown as NaN (not summed up correctly).
I ''fixed it'' (only better error handling - not really investigated the reason) with:
...+ if(cmds[j].extrusion > 0) totalFilament+=cmds[j].extrusion;
...- printTime += printTimeAdd;
...+ if (printTimeAdd > 0) printTime += printTimeAdd;
Example .gcode can be found at: [http://pastebin.com/AbGFDyTM]
Thumbs Up! to the Project after all.