What is the best resolution/device size for the spec sheet to JPEG output?
By default it's set to 600 x 800 which is rather small. The best resolution for an 8 1/2 by 11 sheet is 1600 x 2400. If the spec sheet is at a landscape orientation, set the device size to 2400 x 1600.
You can make these changes in Options > Outputs > Artios > Bitmap output > Spec. Sheet #1 to *.jpg file and go into the Position tab.