Thanks for the update, but seems the scroll issue is still present in BitWig 4.x, it was all working great at first then after a few navigations and group/category selection and then preset selections, it's back to it's old sticking and starting functionality. The old trick of navigating out or over other areas of the vst doesn't seem restore functionality as quickly anymore but if you wait or go to use the scroll bar it comes back to life. Is this functionality tied into mouse movement in some way? Maybe put the programming in a low polled event loop or in a loop but only to execute when certain flags and conditions are not met restoring functionality?
Maybe it's a focus issue, maybe add a debug console which pops out to the right, or bottom to the vst so you can watch the scroll flags/variables and see when things are not what they seem.
Often when I'm programming something visual the standard debugger and the drill down and skip function & variable and function traverse features are not that useful so I often build a visual debug output where I can watch the flags & variables in real time.
Keep track on mouse over, what mouse is over, when wheel is used and focus, might show something.
I often find it's always something small in the code that takes the longest of time to find and fix.
I've noticed that if I don't move the mouse after preset selection that's when it most often stops the mouse wheel from working, if I keep moving the mouse after selection it comes back... Eventually...
RE: Virtual Keyboard keys getting stuck down
Also still there, but this time it actually happened pretty soon after starting ana2.