Scott, the Ecosmart bulbs are detected as “Thing” after you add them. You need to login to the web IDE and change the device type. I’m using “ZigBee White Color Temperature Bulb” for the GU10 white LEDs, and “ZigBee RGBW Bulb” for the A19 color LED bulbs: Changing Device Handler after Install
I just purchased an Ecosmart A19 color LED to check it out. Warm white seems to work fine, using the standard “Smart Lighting” app and choosing “Turn On & Set Color”, and for color “Warm White - Relax”. You can get them back to white if you select a color temperature …it sounds like CORE is a good bet there.