Hello,
some time ago I've the Infinitum PT template extended license and installed it onto 2 services on Joomla 3.6. It works extremely slow on both them, also at the administration bachend. Could you suggest how to improve the performance? Since on your demo sight the template works pretty decently. I tried to diagnose the issue with Page Speed Insight tool for both services but still do not know how to approach it (links for the tool's diagnoses are in special info section).
Regards, KF