yes, running as admin. not sure there's more I can say, "symlink" problem on windows (should be mklink?), "anolis" not present in wine on linux.
the unpractical thing is that it stops at any error and doesn't build anything at all. maybe each build should be treated separately? also it boldly stops when you're offline, even if the cached files are still there and good to go (got isp problems). all in all it seems to only work well when nothing goes wrong ;)
in the end I disabled the non-working builds so I can build for windows/linux on windows, and for linux/mac on linux. I haven't tested the resulting mac build yet, but the others work ok. the only bummer is that I get 200Mb+ worth of files for a 700kb web game. but that's another story ;)