CONTENT FILE LOCKED

Usually the "Content File locked" Steam error indicates that another program prevented Steam from updating certain game files. Especially Avast and AVG are known to cause this issue. Adding the game directory to the exception list should usually do the trick, it's strange that it still does not work in your case Are you maybe using other security software aside from Avast?

You could try this:

• Go to your game directory (rightclick on RW in Steam -> properties -> local files -> browse local files) and delete the executable ("risingworldx64.exe") manually. Now run the Steam update, or alternatively check the game files for integrity. If it still does not work, you could try to delete the whole Rising World directory (but keep the "Worlds" folder if you don't want to lose your existing worlds [same about the "Blueprints" folder])
• Turn off Avast temporarily until Steam has downloaded all game files. If you still get the "Content File locked" error while Avast is disabled, another program is most likely responsible for this issue.