Okay this is absolutely confusing. I have the same problem. I use to be able to run 3 runemate bots at once, then it went down to 2, and now I can only run 1 bot. The others just show the java crash.
UPDATE!!! For those still having this problem.
Clear Java Cache
Clear Runescape Cache
Right...
Currently using 2.5GB with 2 open.
Yes I have the most updated java for 64-bit.
I had all three bots rolling before, I can only have 2 now and can't login with the third one. I haven't changed any settings prior to the crash.
2.5GB with two open.
I have 4GB Ram, its weird cause it was working fine and just stopped letting me run 3 of them.
Update, tried do that method and still didn't allow me to open the third one. Strange.
It has been working fine and suddenly today after restarting my computer I can no longer open 3 instances of runemate. I currently have two open but for some reason when I open the third one and log into runescape it crashes. What could be the problem?
I have tried re-installing Java. Still...