ModSelector Error 8.0.0

I just downloaded the modselector, and unzipped it. Whenever I try to open the .jar (There aren't any spaces in the location) it opens for a fraction of a second, then closes right away. Anyone know what's wrong?

No idea what it can be so I'm going to give you the standard reply, which might or might not help.
To begin with make sure you have the latest version of java installed Verify Java Version

After that do the following http://www.mpgh.net/forum/599-realm-...ml#post7158392

And finally http://www.mpgh.net/forum/599-realm-...ml#post7158981