I don’t know if I can help you. Here I purposefully built a tool for the KeyLab mkII. The code is open, you can consult it.
If you know how to program, I suggest you forget about Duplex and create your own LUA tool, only with what you need. This way you will control all your code and you will not depend on others.
In DAW mode, which one do you use? Have you tried routing it with MCU?
I am currently developing two broad tools that have nothing to do with this (while I wait for the API to update with other missing add-ons, with total uncertainty). However, I plan to go back to the code for my Arturia Keylab mkII tool and refine it even more. So any new information will be great.
For example, I have no idea how to change the keyboard screen names. I don’t know if it can be done using sysex.
However, I don’t want to mix things up. I know you have your problems and I don’t want to be dizzy. With MCU you can have control of almost all physical controllers via LUA and sysex.
By the way, you will not find a better ecosystem than Renoise + LUA tool + a keyboard like this to control the DAW. If the tool is well programmed, the MIDI control far exceeds any other DAW on the market.