How are you trying to build? The files config.guess and config.sub are not in the repository. You can download from https://github.com/galo2099/curlftpfs and build after running autoreconf -fi && automake.
It's been many years, but lastdir - "/" or lastdir - "" don't make sense, so it should be (lastdir - path) ? "/" : ""
Please also use the -v command line flag to get debug output from libcurl.
Do not create empty attributes for tags.