From offical KWA forum, someone posted a resolution regarding the shooting mode unreliability issue. It is not perfect but worth to take a look. It is a simple fix that require users to remove the metal bushing and he also attached a photo to identify the part.
If anyone has suggestion that can improve on the current simple fix, please share your valuable opinion.
Also, the credit card/card board fix is another genius solution to fix the issue. Thank you for sharing !
http://kwausa.com/forums/index.php?showtopic=9270