If you want to add the Tapt switches, you need to use a custom device handler, instructions posted in the following thread:
At some point, the Tapt switches could be recognized by ST as a Zigbee switch, but after an update from Wink this could no longer be used to pair them. Keep in mind that the device type required will not update the status of the switch in the app if you press the switch buttons.
As my two cents, if you are to use the ST hub, get rid of these switches. They are quirky (pun intended) and will go offline randomly. I am down to the last one of these and will be replacing it shortly. Just my two cents.