I've been reading the googles and reading the forums. It seems like SIMOS 18.1, 18.6, and 18.10 are supported, yet 18.2/5 are not due to some technical limitations.

However, I found a github project where someone wrote a flashing tool using the openport 2.0 and it supports 18.1, 18.4, 18.6, and 18.10. This makes me think the "technical issue" with the other 18.X versions may not apply to SIMOS 18.4 since this guy made all of the versions HPT supports functional with the openport, plus specifically 18.4.

Thanks for the consideration!