Kega has problems on Windows 8 and later because it uses old deprecated APIs like DirectDraw. DirectDraw has been deprecated for ages now. I think DirectX 7, which predates Windows XP, was the last version to include it. The reason for this is that graphics hardware has changed drastically since DirectDraw was designed. The fastest way to do 2D graphics on modern hardware is using a 3D API to draw textured quads whereas DirectDraw dates to an era when 2D blitting was king. While I'm not a huge fan of Windows 10 (or 8) some regressions in a really old, long deprecated API are not a particularly good reason not to like it. There are Genesis/MD emulators that are being actively maintained and don't use these old APIs. Is there some reason one of those wouldn't meet your needs?