The i1Profiler user interface (as well as other X-Rite applications: i.e., ColorMunki Photo, ColorMunki Design, ColorMunki Display, i1 Studio, etc...) is based on Qt Framework.
There is a known issue with Wacom tablets and Qt based applications. Wacom tablet mouse clicks are not working in Qt based applications. There are workarounds posted on the Wacom User Forum website. The two simplest workarounds seem to be to switch the tablet mouse to “Pen Mode” or to connect a standard USB or wireless mouse when using the i1Profiler application.