Trapcode Suite has been updated for CC 2015. One problem remains with Sound Keys - it cannot generate new keyframes when run in AE CC 2015. Your old project will load and work fine, it is just new generation that doesn't work. This issue will require a fix from Adobe, they are aware and on it.
Because of this issue we recommend that you keep CC 2014 side by side. The CC 2015 installer by defualt removes any previous installations, so read this before you install CC 2015.