This is patched firmware version 192.04, based on main firmware version 92.04 for the Axpert Max 1 8 kW, with the removable display.
This firmware is for the TMS320F28066 processor, which is the one with the single voltage regulators (see this post). Do not use with other inverter models.
Original VP5K.inv (hex) is dated 2022/Sep/22.
The patches change the version number (will still display as 92.04 on the display), fixes the premature float bug, and implements Georg's patch set for the "stuck at 90V" bug. The minimum MPPT voltage is set at 175 V. For a 200 V version, see patched firmware version 92.06. The MPPT voltage and firmware version are the only differences between this and 92.06.
Use at your own risk.
Edited by Coulomb
Added patch details, links