I recommend creating a ticket with Wowza support my sending an email to
firstname.lastname@example.org to resolve the crashing issue you're having.
As for the "Missing function: xsbwtest" messages, the "Missing function: [function-name]" error in Wowza is usually the result of a Flash application doing NetConnection.call([function-name]) where [function-name] does not exist.
Wowza will ignore the messages that it does not understand but does log them. I recommend checking the log for memory related issues if Wowza is crashing.