So, some further developments if anyone is interested:
Seems the original developer dropped the project but was nice enough to pass it on to another dev that revived the Windows Phone editions. I haven't yet found news on the Windows 8 edition being revived, but I found the source code:
Source [win8/wp8] (snes8x, vba8x, vgbc8x):
Also, I was delighted to discover that, on a Windows 8 PC (not RT, I tried this on a Surface Pro), it will permit you to download the app from the Windows Store if your account already "owns" it. Fortunately I had downloaded it before, so that worked for me! I am totally puzzled as to why it would allow me on the Surface Pro and not my RT. Puzzled and angered! If it is okay on the Pro, then it is an absolutely arbitrary restriction to block it on the RT. Evil.
I'm going to look into side-loading it on the RT. Forgive me for not researching this first, but am I correct that it is possible to side-load windows store apps on a non-jailbroken device? And... another assumption... that Windows Run-Time Apps use the same code on Windows 8 RT and Windows 8, so I could copy the files from the Pro and plop them on the RT? Maybe I'm way off-base here... Not expecting anyone to do the work for me... just kinda announcing my next plan of attack and would welcome any wisdom on the subject.