I've translated the Japanese language strings for the MRZ99 to English.
I figured out the format of the LNG file, dumped the Japanese, translated all the strings using google translate, then rebuilt the file.
Some of the English is not perfect but it makes the system much more usable.
I've tested it with APP firmware version 3.070200 (installed with platform version 3.000600), other versions may not work.
If the old language file is 93627 bytes long then this will almost certainly work.
To install this, unzip the attachment mrz99english.zip and put the PF090JPJPN.LNG file on an sd