I was afraid I was doing something original I'll look into the registry-based system first since I think it shouldn't be too bad to make a program to read data from a COM port and push data to the registry.
Long term, it sounds like it would be a good idea to investigate the SDK to see about developing a plugin and protocol for getting data from a COM port. Is the 3rd party extensions forum the right place to discuss development or is there a better preferred forum?
Sorry for letting this sit. Between other stuff going on and taking a step back to rethink this I let this idea sit.
I would like to at least consider the shared memory approach. Is this something that would require the HWiNFO SDK and some sort of licensing agreement? If that's the case, would it be better to take this conversation to email to see if there are terms favorable for developing this on a hobbyist budget and what type of software licenses are suitable for this type of code?