Problems reading the G-code file

I used this G-code file:

cartridge.nc (31.3 KB)

and usually it works fine. But sometimes it shows the error “ERROR (4): GBRL ERROR: G-code words consist of a letter and a value. Letter was not found.”:

Carbid Motion was running for some time and I clicked multiple times the Start button (drilling some holes in a dozen cases) and then it stopped with this error. I restarted the program and the same file works fine again.

PS: would be really nice if it would remember the last directory when I click “LOAD NEW FILE”.