Hi,
I was the original poster of binaries for the standalone freerouter on the N8VEM website. There were some questions as to the appropriateness of posting them (see the forum on the freerouting.net website or search this group,) so Andrew took them down. I agree with him. I haven't seen anything posted on the freerouting.net forum or the kicad-users forum on Yahoo that indicates the situation has changed. Alfons Wirth (the author of freerouting) has posted on those sites previously.
As far as Java, the compilers use hot-spot technology to compile the byte-code down to native machine language. So, the only slowdown you get from writing something in Java compared to something in C or C++ is the algorithm and the overhead associated with object-orientation. You can write slow code in any language.
Michael