>I'm primarily searching for a way to do it client-side-only.
>I want to make it easy and hopefully cross-platform...

The proprietary comms protocol pretty much eliminates the "cross-platform" hopes. I suppose a port of JEmplode would do much of it, though.

But seriously, porting kftpd.c (ftp & web servers) to the Central should be very easy if it's running Linux... like, perhaps an hour of my time given the existing kernel source tree for the Central. *That* easy.

Cheers