Can I print several imprints at one time?

Yes. You can add several imprints to the printing queue which are sent sequentially to the e-mark. If needed, this queue of imprints can run in a loop and start always from the beginning again. For that activate 'continual marking' on the e-mark connect page. 
 
 
 
 
 
Another option is to send the imprints directly from My Imprints. Just click on the e-mark symbol and when you are connected, it is immediately sent to the e-mark.