Still no luck on Windows XP SP3. My last resort is to do a factory reset on the machine, get everything back up to date (windows updates, etc), and try a clean install on a clean machine. The only variable I haven't removed is the fact I downloaded the ZIP on Windows 10, extracted on Windows 10, and am trying to install that extraction on WIN XP. When I do my factory reset, I will download the ZIP on my WIN XP and extract there, using the default zip program instead of WinRAR or 7Zip. The whole process will take over a day, especially with windows updates... if you have any other suggestions for a truly clean install (besides the obvious) let me know!
If all else fails, I will just install 1.9 again, which did work on my WIN XP when I first joined here (I even got permission to upload partitions of the 1.9 download back then). I would really love to play your new SP campaign and finish it
Thanks for the continued support everyone!