I forgot to include the answer to a previous question. The small circle in the upper right corner of a device definition that gets to the various device configuration screens is used from the initial Device view screen (Areas) of the Harmony client. These are device specific configuration screens rather than scene specific device screens which is why I think you do not see them from Scene management. Go back to the Areas screen to define specific device information.
To keep the last series of posts current, I was able to confirm that devices with types “ICONSwitch-Dimmer” and “SwitchLincV2-Dimmer-600w” do not appear in the Available Responders list for Scene creation at Harmony client level 0.19.6. The devices with LampLinc variations and KeypadLinc variations did appear in the Available Responders list.