I dived into the API which is locally accessible on Tahoma… it’s not super complicated but takes some time. Then I used the driver in this thread to make the GET requests for “up”, “down”, “pause”. Next I made a virtual device for each shutter using this virtual device creator (used the “window shade” device type).
The API documentation and how to activate it are here.
Another option, that I discovered later is to use Home Assistant, which can be installed on a local machine, and some NAS devices actually have it included (Synology, Amber, etc). I ended up getting an Amber and realized it came with Home Assistant after I did all the work, but with Home Assistant it has a built-in integration that works great.
So either you’ll spend some time creating quasi virtual blinds, with tedious REST API commands (not so hard just takes time), or spend about $250 on a NAS with Home Assistant built-in… or end up doing what I did and do both by accident 
but I’m happy with it all, much better than the old DTH.