print not starting on layer 1

Hi
here is what happens

i design something in sketchup export stl file, add to mc (matter control) then i adjust the ratio and align to bed then export to g-code for printing.

when i check in mc in 2d or 3d view there is nothing in the first layer sometimes nothing appears to layer 4 or 5 and if i try to print it prints in the air messing up the whole print, because the skirt looks great then it is too late to adjust when item starts.

has anyone else seen this?

is ther a way to view slicer output in cura i have not found it.

thanks

 

i just opened the stl file created in mc into cura then exported gcode. when i open gcode in mc to view there is nothing in layer 1.

 

using a mac with 10.10 trying to figure out how to fully uninistall app to get fresh preferences but no luck yet