screen sharing from Windows to Mac over LAN

Solution 1:

According to Real VNC support, this is a 10.7 issue. I sort of confirmed it by successfully using Real VNC to connect to 10.6.8 and 10.9.3 hosts. Regretfully my Mac Pro (2,1) is too old in the tooth for OS X 10.9.x, so I have to figure out a different solution.