It's taken me a while to figure out how to configure the Qunexus in order to get some reasonable control over keyboard velocity.
I've found the following process to work fairly well
1. Reset all the key gains to normal
2. Set the note gain to 1.00, curve=linear, and set min = 0, max = 127 and offset = 20
3. Set the overall sensitivity to 0.75, on threshold = 2, off threshold = 1
Now try a patch (like a piano) with a reasonably wide dynamic range where you can also hear the timbre change with velocity. You should find the keyboard fairly controllable. The trick here is the offset value which ensures that a minimum velocity is obtained from light touches. Without this, I found the keyboard almost impossible to control accurately, with missing notes regularly occurring. A real physical keyboard actually has a minimum velocity, anyway, so this is a good compromise.
A few notes may now be under or over-sensitive. Try correcting this with the individual key gain settings but be prepared for disappointment. Some keys, particularly under-sensitive ones, simply can't be corrected for.
But don't worry. I know how to resolve this, though it will require some more work with a Reaper JS plugin. This will allow under-sensitive notes to be scaled appropriately to resolve the issue. I'll post some code and instructions shortly.
Once I've gotten all the quirks resolved, I intend to propose to KMI that some kind of VST plugin to process MIDI events from the Qunexus might be the easiest way to resolve some of the current issues. (since many of you, of course, will be using other hosts than Reaper, where the problems are so easily fixable).
In addition, I'm hoping I can persuade the engineers to produce a version of the firmware where the initial tilt timeout is either disabled or minimised. At present this delay seriously compromises the use of keyboard tilt for bend or modulation, because the delay is so long in musical terms. I appreciate it was added to attempt to mitigate the tilt control problems that the engineers must have seen during product development, but the flaw lies in the algorithms chosen, not the hardware, so with the changes I've implemented, the delay is no longer required and if eliminated will allow a lot more flexibility in playing styles.