Sharing some progress I made…
It seems to use the OJ Microline back-end service, and I’ve been able to connect that integration to my Ditra Heat E R6 thermostat.
I followed this thread MWD5 WiFi thermostat (OJ Electronics/Microtemp) - #92 by paglatz and used customer ID 3 (not 33 as shown in the phone app). The Ditra Heat E R6 Thermostat now shows up in HA as an OWD5 by OJ Electronics, with sensors and a control. Will test and see what works!