From the homepage:
"A new version of SMS Plus is available, the big addition being legacy video mode (TMS9918) emulation for both the SMS and GameGear displays. This was written while I did extensive testing on a SMS 2 and GameGear, so I feel it's fairly accurate. I have included a very preliminary Windows port that I used during development, but it's not the kind of thing you'd use for any serious gaming".
Get it here: