For at least sylenth1 2.21 on win 10 you can fix that demo notification by reinstalling it and setting the .exe file compatibility to windows 8, which you can do by right clicking the install exe file, clicking properties, then go into compatibility tab. This at least worked for me

Win 10 1803 caused a new problem with the 64 bit version where it locks up. If you use FL you can at least switch it to 32 bit and have it replace the 64 bit version

 

Last edited: May 25, 2018

I can confirm that this procedure works even on Windows 10 creators update:
- download lennar.digital.sylenth1.v2.2.1.x.installer.2018.02.18.x86.x64-aon
*- rightclick , properties, set compatibility mode to Windows 8
*- open as admin
- install 32bit Version and Bridge via jbride

No "thank you for using this demo" nor crashes !


(* don't know if These steps are needed)