The error aside, you DO NEED a blackberry data plan if you want to use the blackberry-branded data apps on the mobile network AND on wifi. You may be able to use the hotspot/wifi browser, and sounds like you were. Make sure your default browser is set to the wifi (or hotspot) browser in the device options. But understand, you will not be able to use the push email nor blackberry messenger without a blackberry data plan.
There is no user setup/configuration to speak of. This is done by service books which are pushed to the device when you activate a blackberry data plan. The exception is setting the APN for using carrier data. See How to use BlackBerry on Generic Data Plan - BlackBerryFAQ