I have the same MBP as you. I haven't tried 1.15 but OB wasn't working for me on 1.10.
Actually it was kinda strange. It worked during several hours, but I had to do things in a special order.
Like having the Control Panel launched and USB cable plugged before I set my AK in OB mode.
Otherwise I would get kernel panics and had to restart my laptop.
Then it would get even worse. I managed to set it in Ableton but I wasn't able to see my whole +Drive library in OB and changing a parameter in the plugin resulted in kernel panics too.
Support team told me it was indeed a common problem with Core2Duo computers. It was back in september, but I guess they haven't found a workaround.
It's quite a weird issue ... All DAWs are compatible with these systems..
Whatever I spared some money and bought a new 15" MPB. It was time for an update anyway, but not everybody can afford it... I'm still waiting for it to be delivered, but I hope it will work!
I just saw that they highlighted that Core2Duo systems aren't supported. A few months ago, I only found this information on the support page. It's a good thing they added it. They would be inspired to find a workaround because new 13" MPB and other systems still come out with Core2Duos.