I wonder how to express the combination of the dimmer on the Par64 and the XPress 19 in Capture. In the Titan sw we patches the XPress 19 with a so called Pending Dimmer. (described in the Titan v11.0 manual on page 91.)
Once you have a Par64 in your showfile you drag and drop the Xpress from the library tab onto it. This way you attach an accessory to a fixture.