If it can help, I just finished a Home Assistant custom component that can read pretty much all the Midnite Classic's registers and more and create corresponding sensors/entities in Home Assistant that can be used to control and chart stuff and feed the nice Sunsync power flow chart.
The custom component is in GitHub at https://github.com/qcda1/ha_midnite_classic
At installation, the user can select the values he want to be created as entities in HA from a total of 54 from which 11 are selected by default. The sampling period can be specified from 30s to 1 hour. The Classic must be on the same LAN than HA and a host name should be configured as this will be the name of the equipment in HA.
Attached is a sample installation picture:
Regards,
Daniel.