Images and text on z6 game are upside-down and backwards

I'm attempting to play ARTHUR.z6 with ARTHUR.blb but the images and the text are rendering upside-down and backwards. I'm running this on on a MacBook Air with the Apple M2 processor and OSX 15.6.1 using Zoom 1.1.6. I tried several other games and z5 and earlier seem fine.