ArtRage rotates the canvas to fit the device when you open a painting so it's possible that the painting was created in portrait orientation, but adjusted the canvas to fit the longest edge of the device when opened so appeared landscape. There isn't a way to make the script play back at a different orientation to the one it was recorded in, but after it has finished playing back you can rotate the painting (not just the canvas) using the Rotate options in the ArtRage Edit Menu. The canvas rotation you applied at the start of the script just rotates the painting surface, not the final image itself.

We'll look at ways we can more clearly indicate the actual orientation of the painting when you create it for a future update.