According to the following test report from Crestron, it looks as though that driver is a forward phase driver. The SELV dimmer that you are using is a reverse phase dimmer. It also mentions on that report that reverse phase dimming will cause flicker. We would recommend putting a forward phase dimmer on that circuit. Unfortunately we are unable to recommend a dimmer that will work because we have not tested that particular driver. We would suggest contacting Crestron to see if they can recommend the correct dimmer for that driver.
http://www.crestron.com/downloads/pd...sults/1749.pdf