Hi,
Have you verified that your KBI is configured properly? Might be worth testing it in Run mode by toggling an LED when the KBI is active. Once you know that the KBI is OK, then try entering Wait mode. Debugging can be done using GPIO, toggling an LED, or watching the current consumption of the MCU when in Wait mode. The RS08KA goes into and comes out of the low power modes without too many problems. If you continue to have problems please post a code sample.
Thanks,
Rick