 
In case anyone is still having problems with the SP4 pen on Roll20, I've just found a post in Reddit with the solution.   The short answer is open command promt and run :  reg add HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Pen /v LegacyPenInteractionModel /t REG_DWORD /d 1 /f  
 Controlling pen behavior in Windows 10    
 
				
			