If you are using a pen and tablet with Windows 10, you may be getting unwanted moving of the main program window and/or scrolling.
The cause is "Windows ink" interpreting your pen movements and sending unwanted messages to the program. It can be fixed as follows:
There should be a windows ink icon on your windows taskbar. Left click and then click the two dots to get more. Then click settings.
In the Windows ink settings, check the box "Use pen as mouse in some applications".
It should then be fixed.