how about VNC?
VNC is not included in the zip, you can download it for free from http://www.uvnc.com or other vnc sites.
And the ls remote is telling me to open port 5900 on the client computers
This is the default port used by the "pushed" vnc server, you can change the port used from the options if you have already a vnc server running.
Where does the screengrabber save the .jpg?
are they supposed to pop-up automatically?
It is saved in the %temp% folder and should popup automatically.