Cant you put all the natives in the jar folder, so then everyone could execute the jar without having to configure java.library.path
I did this to run it on linux:
java -Djava.library.path=natives-linux/ -jar cygear.jar
They're all already in there it seems. Also there is a run-script for linux, so you don't have to do that.
Add a webstart/applet, easier to test for us
Downloading something isn't a deal breaker anywhere else except JGO and flash sites. JWS and Applets both suck, but maybe I will use them when they don't.