Many years ago I played around with the rounded corners in InterForm400 and found out how to create some ‘funny’ shapes including circles with the frame element when using rounded corners. You can sometimes use this trick to avoid using an image. Please notice, that this trick is not supported for ZPL and IPL output (rounded corners are printed as sharp in ZPL and IPL).
To create a circle you simply should set the height and width of the frame to the same value and set the radius of the corners to half the height/width. The same is of course possible in InterFormNG, but in InterFormNG the circles can be as large as you want. I include an export for InterForm400 (export.cir) and a template with a “snowman” created in InterFormNG (circles.itpl) for those interested.