I just bought this game and the print feature in the automap does not work. Is this because it running on a modern system? Or do I have to install something first?

You'd somehow have to tell DOSBox to send the data to your printer. No idea how that works these days.

If you're really motivated to get this working, these pages have some good tips:

http://blog.dummzeuch.de/2014/03/03/printing-from-dosbox/

http://superuser.com/questions/270457/how-can-i-print-with-dosbox

Short answer is that you need to install a modified version of DOSBox and then update the configuration file to direct the output somewhere.