I just downloaded the Mac version of 3DNes 1.4.0 last night, but a major color/rendering problem is making it virtually unplayable. A lot of the backgrounds & objects have the wrong colors or missing textures, and every animated sprite is just solid gray. It's done this with every game I've tried (Mario/Duck Hunt, Mega Man, Super Dodge Ball, etc.), so I'm pretty sure the individual game is irrelevant. I also downloaded a free game that uses Unity (Tailgunner) and it worked fine so I don't think it's an issue with my computer using Unity. I don't know if this was an issue on earlier versions of 3DNes, and I couldn't find an earlier version to download to test it.
Computer - Mid-2011 21.5" iMac (2.8 GHz i7); OS - El Capitan (10.11.6); Video Card - AMD Radeon HD 6770M (512 MB)
I'm also running Sophos Anti-Virus, if that matters. Here are a couple screenshots that show the issue: