The settings represent what capabilities the hardware supports. From my observation in switch mode it would turn on/off immediately from the manual control, but in smartthings/zwave it would still behave like a dimmer.
For the association, what group are you using? 2 is for single click and 3 is for double. Check the data section in the groovy ide for the device and ensure associationGroup1, associationGroup2, associationGroup3 and supportedGroupings are there. The 1st 3 maybe , the supportedGroupings should be 3. Also verify groups is 3 in current states. If these are not present select “Sync Associations” from the settings in the app. This will force the updates, I noticed sometimes the device doesn’t respond to all the commands on install (not sure if too many commands). You can avoid the associations and use automations to achieve the same using the scene controller device. I personally used the associations for other zwave devices. My reasoning was in case the hub fails I would have some of the available functionality.
Please make sure you are using the latest version, I made some changes and fixed a few bugs along the way. It should work with the new app UI.