S4 - SideSync 4.0 connection fails when I try to see screen on PC

[AC Question]

OK, I'll admit it - I rooted my S4.... AT&T I337 Just found the SideSync app and want to use it. It installs fine and phone and PC link, but I get "connection failed" anytime I try to bring the phone screen up on the PC. Strangely, I can play audio, launch pograms, etc. from the PC. Just can't see the phone screen. Any ideas?