ERROR NAME; configurationerror COMMAND; setpagedevice OPERAND STACK; --dicttype--
Printing to file (pdf or ps) and then printing with another program works.
Install or unpack the latest Windows driver. Search for a file called BM7820N.PPD and copy it over the /etc/cups/ppd/YourPrinterName.ppd
It seems that the GPL'd drivers are way too old!