And the final test would be to create a brand new file and try printing with these settings and printer to see if it also crashes. That rules out issues with your file.
All in all, this looks like something to report over in Report an Issue as a possible bug in FileMaker or the current printer driver.
(FileMaker Inc. uses Dymo printers at their head quarters to print visitor badges so I think they'll be very interested in any issues that affect FileMaker's ability to work with this printer.)
Thanks for your input.
Will give that a try and report back.