There are several programs that can accept files from the MAXX-HD and convert them to other formats, and create MAXX-HD compatible files from other types:
The Edius non-linear editor from Grass Valley Group is a full featured editor that can work directly in JPEG-2000 format and create various output file types. http://www.grassvalley.com/products/edius_pro_7
Telestream Vantage (and it predecessor Flip Factory) can both handle MAXX-HD transcoding: http://www.telestream.net/vantage/overview.htm
Ipera Technology’s Pixelxtream: http://iperatech.com/products/pixel-xtream-software/
Amberfin iCR: http://www.amberfin.com/products/icr-full-transcoder
There are no plugins available for Premiere. Telestream Vantage is the only system that uses the .vcf file format as they supported the MAXX before the .mxf export capability was implemented.
The Edius editor from Grass Valley will accept files from the MAXX in the .mxf format. These are available when logging into the MAXX with the username mxf and the password mxf (as opposed to anonymous login. If your unit does not accept this login then you need to update the system software.)