Altho i haven't used savant before, i would imagine the integration process would be similar to other control systems.
The Lutron QSPS enclosure is likely connected to a Lutron HQP6 Processor via
QS-Link, and the processor is connected via Ethernet to the home network.
Savant should have an IP Driver to talk to the Processor. You would have to create phantom keypads in the Homeworks QS software and use the "Phantom Buttons" to assign your UP,DOWN and STOP commands, once the that is done you are going to need the Lutron Integration File generated from the HomeworksQS software, it wil have all the button map IDs needed that you are going to have to input into the driver for Savant.

Hope this helps