I looked at your picture and downloaded the file. One thing I think Dick hit on the head is the size. You have too much in too small a space. If you look at the letters in Designer there are places that don't show carving anything or very little. Look in the center of the "A" and you can see the center closed in area is barely showing to carve at all. The area is too small for the bit to cut. There are very small spaces between the letters that show only partial depth again due to the bit being too big to fit into the area to carve. Making the pattern 8" diameter cleaned up a lot of the partially carved areas around the letters and the before uncarved area in the "A" now looks correct.
If you cannot enlarge the pattern, you may try using the 1/32" bit to keep the details. Try changing the bit in Designer to the 1/32" carving bit and see the difference in what Designer shows you.
A Series machine purchased in 2007
had 30 minutes running time up till 2-13-15
Ring Neck Blues DC Insert (outstanding job keeping machine clean!), HF DC blower
Designer 3.102, Pattern Editor, Pattern Sculptor, STL Importer, Scanning Probe, 2D Vector Drawing Suite, 3D Pattern Modeling Suite, Centerline text, Conforming Vectors, CarveTight Chuck, Decorative Bit set
Universal Laser ILS series laser engraver with dual laser cartridges 135 watts total with 24" x 48" table and Class 4 module