With Windows 10, by default, when you install Clip Studio, it will default to using TabletPC (Windows Ink).  If you have changed it, and you are now having issues with Clip Studio Paint, I suggest that you change it back to Tablet PC and then test it.  

To do that, follow the instructions below. 


Open Clip Studio Paint, then click on File. Scroll down to Preferences and select it. 
[1] Select Tablet. This will open the Tablet features dialog box.

[2] Select Tablet PC, click OK, and test.