The 'Use Windows Ink' option must be enabled in the tablet driver, if Photoshop CC should use it.
Other Photoshop versions looked into 'Wintab', newer version look into 'Windows Ink'. (Note: if you had another tablet before, you may have another, old wintab file still on the system, that needs to be removed before it can be overwritten by new driver installation.) The application is responsible to pick the pressure data from one of these buckets. There are 2 different 'buckets', one is called Windows Ink, the other 'Wintab'. For pressure in application please understand that the driver puts the pressure info in a 'bucket', where it has to be picked up and used by the application. That should make sure that the hardware is ok. In the detailed/advanced settings you can move to top pressure threshold down to get maximium pressure without access physical pressure on the pen. If you need to press too hard, you can adjust the tip feel slider. You can check the pen detection and pressure there - also in the pen settings. If you have access, click on About then diagnose. It will warn you, if the driver is not working or the tablet not detected. First open the tablet control panel or Wacom Desktop Center.
