There's an mplabx command-line tool 'ipecmd.exe' supposedly similar to 'pk3cmd.exe' that sounds like it should work with any of the programmers,
and it has a PKOB setting. There's a readme in the docs folder. Might be worth trying that w/the curiosity.
thanks it's alive
the ipecmd command line utility can be used to program your curiosity board from mcs ide

programmer filename ipecmd.exe
command line -tSBURxxxxxxxxx -p$target-device$ -f$hex-filename$ -e -m


where BURxxxxxxxxx is the serial no of your curiosity pkob

it works very nicely