OMG thank you for your help!!! now it works and runs fine!
Thank You!

I have a windows 7, its 64 bit too.
 I just reinstalled java a couple of days ago (minecraft problems) so my java is up to date.
 I didnt mess with the directory i installed it too so its located in [computer - Local Disk (C:) - users - (username) - Downloads]
 I run it by just opening the zip file, going into the mythruna file and running it.
Plus When I saw that didnt work i extracted it and sadly the same thing happened

Ok, so i have an error before ANYTHING happens. Whenever i run mythruna i get this:


Could not find the main class: mythruna.client.Mainstart


Somebody help me solve this error please! I have searched everywhere for a solution and have not found one at all.
i tried reinstalling it several times also.
Help Please!