Photoshop CC 2014 - Liquify lags/stutters with pen

Question

Since installing Photoshop CC Version 2014  yesterday the liquify tool is behaving strangely for me. Moving the Brush Cursor seems laggy/stuttering (hard to describe).. it works 'ok' with a mouse but once i started using the pen it's really laggy.
If you smudge in one direction the smudge appears with a short delay, after that - if you still pressing the pen down - it works fluently. But if i remove the pen and press it again on my tablet surce it lags again at first... So it's very hard to use it properly.
I Tried the 'old' photoshop CC and CS6 (both downloaded from Creative Cloud and still installed) and both still work fine and fluid.
I'm using Windows 8.1. 64-bit on a Core i7-3770k, 16GB Ram, Gainward Phantom GTX770 graphics card.
Is Anyone else having this problem? or does anyone knows what's causing this?
(if it's a graphic driver problem, why is it still working on photoshop cc, it seems the code for liquify has changed for version 2014).

Answer 1

I do not have Windows 8 but have seen the following about Windows 8 and Photoshop CC 2014 pen support in an other tread;
Photoshop CC 2014 changes stylus use to use Microsoft system API's, with these API's you need to have Windows Ink enabled. These API's give better stroke results and improve the out of the box experience for users using Windows tablet/convertible devices. If you want to go back to the old WinTab implementation of previous versions do the following:
Create a file that contains instructions to revert to the WinTab functionality.
Create a text file in a text editor such as Notepad.
Type in the following lines:
# Use WinTab
UseSystemStylus 0
Save the file as a plain text file named PSUserConfig.txt, and save the file into the Photoshop settings folder: C:\Users\[User Name]\AppData\Roaming\Adobe\Adobe Photoshop CC 2014\Adobe Photoshop CC 2014 Settings\.
To turn off the gestalt's functionality, delete the PSUSerConfig.txt file. Or, move it to a different folder if it doesn't contain any other commands, or change the lines so they read:
# Use Win8 native tablet support
UseSystemStylus 1