[juliansader]

Originally Posted by MikComposer

That's nice you wrote this script. Those script with interface tend to hide behind editor unfortunately.

REAPER does not currently add "pin on top" buttons to script GUIs. However, there are two easy ways to keep this script on top:
* Click the "Dock" button in the GUI to dock the script, and then pin the docker on top.
* Install 3rd party software such as FileBox eXtender, which can add "pin on top" as well as other useful buttons to windows. (I personally use FileBox eXtender, and it is very useful for pinning any window - even non-REAPER windows such as media players - on top while I am working.)

Originally Posted by MikComposer

And proof is in the pudding; you yourself don't seam to know how to do that, yet you say I'm the problem:

Some people are problem solvers, others are problem-seeking complainers.

Originally Posted by MikComposer

there isn't even an action to add to toolbar to set mouse modifier to insert note on single click. The only way to do that is trough modifiers in preferences. Fine, but why it affects cc lane? It shouldn't.

If I understand you correctly, you can try adding the Action "Set default mouse modifier action for "MIDI piano roll left click" to "Insert note, leaving other notes selected" to the toolbar. The mouse action "Insert note, leaving other notes selected" should not affect anything in the CC lane.

Originally Posted by MikComposer

So how then I reverse it back to deselecting notes and cc's on on click? I can't.

If you want to do it via the toolbar, link "Set default mouse modifier action for "MIDI piano roll left click" to "Deselect all notes and move edit cursor" (factory default)" to a button.