If the engine or the interface application ask for a system update at every start, then there are some permission issues. For solving this problem please follow these steps:

• Quit the engine and/ot the interface of just:in multi
• Go to /Library/PreferencePanes
• Delete the ToolsonAir pref pane
• Start the engine again
• Enter your pw for the last time (system update)

Then this problem should be solved. If you are still seeing this issue, please create a ticket.