This is what I've been able to do:
-Download the latest installer for Sketchup Make 2015 (and not Pro, as it won't work with this). The location is not obvious from the front page. Download | SketchUp
-Modify the contents of SketchUp.lic (%ProgramData%\SketchUp\SketchUp 2015). The first line should be this:
##NonCommercialUse,NoTrial
And away you go.