This error isn't anything to worry about. Basically, the Updater has some bad implementations in it because it tries to clean up after itself, but it doesn't check if a file is ReadOnly before it tries to delete the File. This bad practices is causing an exception to be thrown and Mastahg isn't handling the exception so it's making the app crash after it updates. This issue has been happening since this bot was still in Beta and Mastahg hasn't deemed it worth his time to fix. If you want to make sure that you don't get this error, then Right Click on your RB folder and go to Properties. Then uncheck the ReadOnly checkbox at the bottom. If you do this before updating, you won't have an issue.
