As the Hoff and Troy suggest J, the alternatives now for K3 are better.
I used to love K3 but now use PHD for the refinement if needed (permanent
setup) and Sharpcap or Craterlet(which btw you suggested to me

) for capture.
Sharpcap does Lx well, so does WxAstrocapture.
Sharpcap also has a better live histogram and on-the-fly mini stacking
so you can find DSOs etc better while framing.
WcCtrl handles the presets and favourite driver settings well, working
alongside.
Steve