Painter 2015: Impasto panel is not all grayed out for Particle Brushes

Description of problem:

1. Launch Painter and create a new document
2. Select a particle brush
3. Open Brush Controls (Ctrl+B or Window > Show Brush Controls)
4. Activate the Impasto palette
5. Change Impasto settings

Result:

Impasto controls (such as "paint to") are enabled.

Since Impasto is not supported, the panel's controls should be disabled

Solution:

The new particle brushes for Painter 2015 do not support Impasto.