Due to the number of breaking changes in the 2022.12.1 code, when upgrading from 0.6.4 you need to remove the Integration from the Integration page before updating, then re add the Integration following restarting Home Assistant.
Altered plugin_path to work on different Installation types.
The following is generated in the error log, until the Integration is removed from the Integration page and re-added:
2022-12-22 15:27:59.537 WARNING (MainThread) [custom_components.solax_modbus] converting old style plugin name custom_components/solax_modbus/plugin_xyz.py to new style short name xyz