taterto - it's actually working, I think. Mine doesn't always turn green when I do a dump. The error message is actually confirmation to you that it worked, the error message SHOULD be there, then it SHOULD crash.
Just go back to your game, save and quit, power off your console, then go plug in your SD card to your PC, and you should find the acnlram.bin there in the root -- if not, did you make sure to copy the acnldump.bin and acnlinjc.bin to the root of your SD card before putting your game in and trying to dump the RAM? Those files are critical and must be present for it to work. They are available on the first page of this thread.