FWIW I got the exact same error "<drive path> not found. Please ensure you are running from a propery configured task sequence". Even the word "propery" was the same mispelling. What I did was manually create the <drive path> in the drive I was booting to, in my case it was in the Prestage Media wim file. I created the <drive path> which was C:\_SMSTaskSequence and the prestage media was able to finish booting and completed the rest of my OSD without issue. I'm not sure why this problem happened but it could be a workaround.