toon boom harmony 14 slow brush stroke drawing

I just update the new toon boom harmony 14, and its too lagging when I use Wacom Cintiq pen draw on my Cintiq. it will take 1 or 2 second to display the stroke after I draw.
However, it’s smooth when I use my mouse to draw, but I guess not many people only use mouse to draw. I use iMac OS X EI Capitan, 2013. Memery :32 GB MHz DDR3
Graphics: NVIDIA GeForce GTX 780M 4096 MB. dose anyone has the same issue and knows how to fix it? The lagging drives me crazy!!

I have the same problem with my Toon Boom Harmony (and Cintiq), except when I try to use my mouse to draw, it still lags. Mac OS X El Capitan, memory 16 GB 1600 MHz DDR3, graphics AMD Radeon R9 M370X 2048 MB. I wish I knew how to fix it, somebody please help! Thank you!

If there are multiple monitors each using Retina or High-Resolution display or
if there are other program and web pages loaded - it may be the graphic card
running out of resources.

If it’s a laptop system there are sometimes power-saver features that put the
graphic card in low-performance mode to conserver battery power if you are
not plugged-into a power outlet.

Beyond that, contact support to have a look on your system.