By version number and the short range probably this is some bug fix. The automatic translation of changelist says:
Changes and the like of the OSD menu, including the last update. Please, check the following contents before upgrading.
17 May, fixes 2016:
<CPU View. The 2.03>
■ was provisionally corresponding to analog RGB signal from PC-8801mkII MR later.
The RGB input of the PC-8801 and FRAMEMEISTER, D-sub15 pin (in two steps) → FRAMEMEISTER connected via a direct cable, output resolution: 1920 * 1080, screen mode: When you x 1 smart to coincide with the time clock has been adjusted. ※ D-sub15 pin (in two steps) → Direct cable FRAMEMEISTER is available in the direct store it is.