"Any experience of the same problem? "
I just downloaded RB-Gain-HotKey.zip to my desktop - ran it - hit ctrl g - it brought up the gain window of real band in win 10.

this is what it is doing
it was running in the system tray as "H" if you right click it in the system tray then select Edit script:

;Gain Change
~Ctrl & G::
Macro9:
WinActivate, ahk_class RealBand ; Selects real band
Sleep, 500
Send, {F10 1} ; Brings the menu up
Sleep, 100
Send, {Right 1} ; Moves over to Edit menu
Sleep, 100
Send, {Down 1} ; Down to Edit menu items
Sleep, 100
Send, {S 1} ; Down to Effects
Sleep, 100
Send, {G 1} ; Down to Gate
Sleep, 100
Send, {G 1} ; Down to Graphic EQ
Sleep, 100
Send, {G 1} ; Down to Gain
Sleep, 100
Send, {Enter 1} ; Hits enter key once
Return

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