Sounds like you've got a nice dev setup - glad it works! Thanks for your effort, even if you travel, really appreciated! I wish I had some setup to be able to at least intercept some Zigbee messages as it seems to require literally reverse engineering Tuya device 
I updated the driver and toggle works fine, and it seems that minLevel and maxLevel work within HE level setting but does not seem to affect the dimmer itself. Though I'm not sure about what physical switch displays because it's a bit confusing. Here is the situation:
minLevel=30 maxLevel=100
- I start from level 100% (level=100 via current states)
- I dim via HE to 50% (level=50 via current states) but physical switch shows something around 70% (which seems to actually be right, as it should be half of 70% range + 30% base)
- I dim via HE to 20% (level=20 via current states) but physical switch shows value around 50%, which again is correct if we take scaling into account, but the physical switches state is now different because it's actually not at 20% but 50%
I will check the code but I suppose the state at this point is scaled both when it's sent to the device and received from device, right?
So setting via HE works but the other way around, via dimmer, still works the old way (but is interpreted by HE differently now because of scaling). I wish I had Tuya hub + App to be able to confirm what's the min/max scaling that's saved in the dimmer, as it would be great if I could make it work within the actual range, and not cap at 50% below which it's just dark.
