How do I print to bullzip from the command prompt

[spearce]

I'm trying to automate converting text files to pdf with a superimposed image. Bullzip does this fine, but how do I call "bullzip" from the windows command prompt?

I set the bullzip as my default printer and then used the print command, but the process hung.
I tried print /d:bullzip but that gave me an error.

Any assistance is appreciated.

Stuart.