When I ran it from the command prompt from the folder I got:
Error: Unable to access jarfile KoLmafia-r15609.jar.
While I was in the folder I noticed the timestamp on the the file was the same as when I first downloaded. I deleted it and redownloaded again (even though I thought I did already) Worked fine. Must of not saved right for some reason when I first downloaded it.
Problem solved.
Probably should of just waited for 15610 like I was going to do, but thought if the file was indeed corrupt you all should know.