Convert does not work with the Premier+2 plugin!
This is a documented bug in the new program. To Convert in Premier+2, one must bring in a design into the Extra module, and export from there (File | Export).
Since the plugin from Premier+ worked perfectly, it made sense to replace the new with the old. BAM! Now it is possible to Convert (i.e., export) embroidery designs using the plugin, without having to take it into Premier+2 first. The only caveat: Make sure to have access to the plugin, so you can install it. If you don’t, simply go to the Portal and download it.