Logic on SL & ML iMacs

I have two iMacs (one late 2011, one brand new) which I use for audio production - one running SL and one running ML (10.8.2).

Im having a few annoying problems moving projects between the two systems. The ML also always gives me a system overload message when using Logic Pro 9 - even though it is much more powerful and has an i5 to the older machines i3. Why would this be?

Cheers

Have you updated to the latest version, which is 9.1.8 (which will run on both 10.6.8 and ML)?

Go to your applications folder on the ML machine and right click (control click if you don't have right click turned on) on the Logic Pro icon then select "get info". Uncheck "open in 32 bit mode".

That way Logic will be able to take advantage of all of the hardware system resources on your machine. This usually gets rid of the system overload message.