Let me just start off by saying I tried searching everywhere, and couldn't find anyone else posting about this problem.
I've successfully downgraded to 1.5.
I couldn't find a program name KXploitpacher (as noted in one of the guides) but I did find NO-KXPLOIT Patcher. Seems to work fine as the creator actually opens.
I have copied the M33Creator folder containing 352.PBP and 150.PBP and EBOOT.PBP to PSP/GAME/.
The creator loads 1.50 OK, Writes 1.50 OK, Reads 3.52 OK, but turns off my PSP after being on Writing 3.52 for about 30 seconds. The first 15 seconds of that I see mem stick activity, last 15 nothing.
I formatted the memory stick and tried the process again, same result. Any ideas?