I recorded a take on piano and tested to make sure it saves properly which it did. I even used Reason 4 with Rewire no issues. I tested some plug ins they all seemed to work. I opened up some sessions that were just audio and some sessions that were just midi and sessions that were both. I recorded a bit of audio, a bit of midi all went smooth.
It didn't require any funny business, on my part, like messing with drivers it all just worked as normal. I had 1 minor hiccup that where a midi track had a bit of a lag but i just quit pro tools and restarted the session and it worked (I have had this hiccup on Snow Leopard so I am not really sure what causes that, I'm still fairly new to this but I don't think its related to Mountain Lion.). It works! Actually works just as well as it did on Snow Leopard. The only reason i took the chance is because I have a Snow Leopard disc so my only risk was $20 bucks. If it doesn't work, you just paid $20 to have to reinstall your previous setup. But things seem to be working OK, so if it's not broke I'm not going to try and fix it.:-) Don't know if anyone else has experienced that and can tell us anything about it. However, when I tried to install, it said that the file was damaged and forced me to eject it. I downloaded the latest drivers referenced earlier in this post. Note that I am only recording stereo piano tracks without plug-ins, so my requirements are simple. However, it did not move the drivers or any other software to the folder and everything seems to be running fine.
The incompatible software folder contains a text file stating that this version of Pro Tools is not compatible with this version of Mac OS X. I am away from home, so have not been able to record anything, but opened and played an existing project. 8.0.5 is still opening and running fine, and the Mbox2 Mini seems to be running fine as well. It was running fine under Lion, and I upgraded to Mountain Lion today.
I am running 8.0.5 LE as well with an Mbox2 Mini. I hope you guys all have the same success. I don't know if an upgrade on to of an existing version of OSX would yield the same results, but I'm very surprised and happy its working for me. I haven't yet tried recording into pro tools with the Mbox2, but this it is working!!! :-) I've got 5 tracks of audio running with compression, eq and fx. I then updated to 8.0.5 and its working fine. This kicked the MBox Micro into life, but Pro Tools LE 8 was quitting at the end of start up. I installed Pro Tools LE 8.0 first which seemed successful, but Mountain Lion wasn't recognizing the PT hardware (currently an MBox2 Micro but I have an MBox2 as well) so I updated the MBox drivers (labelled drivers for Pro Tools 9) from the didgidesign website.
I'm running a late 2008 Unibody Macbook Pro 2.66, but I did a clean install of Mountain Lion on a freshly formatted external 500GB USB Hard Drive to test compatibility with my apps before deciding if I would risk the full upgrade on the laptop. I've just got Pro Tools LE 8.0.5 running successfully on Mountain Lion! :D:D:D