We tried to reach you by email, but it bounced back, so not sure you received the message. Just in case, here's the answer:
We can see you purchased 3DCPrinting license, while trying to activate it on 3DCoat trial install. Please, note 3DCoat and 3DCPrinting have different installation builds. Both are available as trials from our Download section.
Please, install the 3DCPrinting trial and apply your serial key to it. Should make it work then.