I don't have Win 10, but since solution to run C2 under Win 10 is to remove shipped wrapper/s for CD Audio (winmm.dll) and/or IPX <-> TPC/IP (wsock32.dll) I guess you have removed them both, so that's why network play is unavailable.
Try to use updated version of shipped ipxwrapper
or since C1 work fine in network, maybe wrapper from C1 (wsock32.dll) will work with C2?
(It's also recommended to update nGlide
Please, leave your feedback.