There is no reason that the packets sent/received by CU-SeeMe will not
work with SLIP / CSLIP.
PPP is not required.
The Netcruiser software most probably does not support UDP.
The difference between SLIP / CSLIP and PPP is the framing bytes
put around te packet. There is no restriction on which IP packets
can be sent via SLIP / CSLIP.
(By the way, since CU-SeeMe mostly uses UDP, SLIP == CSLIP, since
only TCP connections are compressed.)
You can FTP/WWW, etc., because these use TCP for their connections,
and the netcruiser interface supports TCP connections.
The issue is what IP protocol packets they will process and send, not
how they wrap them on the line. SLIP and PPP are just slightly different
ways of wrapping them.
Yes, people have done CU-SeeMe with SLIP and CSLIP connections.
Alan