Hey Lee Mac,
wasn't sure how to go about sending this to you but I wanted to point it out and let you know about a little bug I found in your TMask routine where you can pass in the intended parameters.
I think i got enough information in the .gif but if you cant recreate it then let me know and I can provide more info!
This may be a bug you were aware about and may not be able to be fixed due to the DXF codes but I figured id throw it out there to let you know!