Light Flickers at Low Levels
Since Crossfades and T8's are Triac dimmable lights, most Triacs require a certain power draw to function correctly. If you notice your light flickering on dimmers, try grouping them into larger groups of lights, if possible.
Also try using a "ghost load" to increase the power draw on the dimmer. This can be done using a small incandescent light that is connected to the same dimmer as the Crossfade or T8 light. Position the incandescent light away from/above the set.