While setting up my controller in Bitwig for MPE operation. I noticed the provided guide only seems to work if you are using VST instruments which have MPE functionality. For the stock instruments in Bitwig which are always MPE enabled, it does not work. Note, I have tried setting the channel to "Same", but the P. Bend range is limited to -24/24, and not the expected -48/48.
Note, I have found a temporary solution, by specifying the controller as "Roger Linn Design -> Linnstrument". This has the benefit of working out of the box, without having to change channel settings constantly. However, I am a bit unsure if this leads to the controller working as it should, especially by using a script for a different vendor and device.
One would assume the Roger Linn Design -> Linnstrument script could be forked and adapted as required. See: https://github.com/bitwig/bitwig-extensions/tree/api-16/src/main/java/com/bitwig/extensions/controllers/roger_linn_design. It would therefore be nice if we could have an official controller script for Bitwig, so there is a more permanent solution.