Laser Calibration for Material

Following the laser manual, I downloaded the back-white contrast file that tests various speeds at 100% power, for the given material:
https://www.stepcraft-systems.com/service/black-contrast-feed-test.nc

As well as the grey-scale test file, which I believe you are supposed to edit to replace the feed rate with the one determined as still producing black from the above configuration file:
https://www.stepcraft-systems.com/service/grey-scale-test.nc

The initial file, black-contrast-feed-test.nc had some odd results for me.
The first two lines were transferred (6mm/sec and 8mm/sec), and then nothing was transferred (laser wasn't turning on) until 36 mm/sec. The laser stayed on correctly for the subsequent 38, 40, 42 and 44mm/sec.
The laser did not turn on for 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, or 34 mm/sec.
Looking at the G-Code, I believe I found the culprit:
Setting power first, then feedrate seems to work (as was the case for the lines that did work), but the lines that didn't work tried to set feedrate first, then power.

Copied from the file:
(feed 6mm/min)
M10 Q255
F360
[snip]
M11
G0 X2 Y0
(feed 8mm/min)
M10 Q255
F480
[snip]
M11
G0 X4 Y0
(feed 10mm/min)
F600
M10 Q255
[snip]
M11
G0 X6 Y0
(feed 12mm/min)
F720
M10 Q255
[snip]
M11
G0 X8 Y0

6mm/min and 8mm/min had worked, but the subsequent ones didn't.
The order is again corrected at 36mm/min, and the laser again works..

Am I the only one this happens for, or is this the bug in the test code that it seems to be?

I'm still trying to sort out the greyscale test file. In the attached photo, the two test jobs are overlapped, and they were done twice (top and bottom). The bottom greyscale test was at full (44mm/sec = F2600), while the top one was at the default 20mm/sec (F1200). The initial left-most portion didn't transfer (laser wasn't on), and I can't sort out why.

I'd be curious to hear others' experiences with this.

Cheers
Thanks