Hi Austin,
I don't use "lift dump". Try "Speed Brakes- Retract full/ extend". Keep in mind that the Spoilers are only available on the ground, and the Air-brake is controlled by the same lever. So, you extend the Air-brake first, then extend them again to activate the Spoilers.
The Emergency Gear Extension system works by clicking like you are. The Access Panel and actual lever are not modeled at this stage.
Thank you,