Not sure on the OS problems, but you need a good graphics card and 8 gigs of ram.
I have in the past with no issues run CS6 on 10.6.8, but not sure about the CS6CC versions which says 10.7 required.
Ordinarily, I run Photoshop 13.0.5 ("CS6") under Lion 10.7.5 on a 65-lb Mac Pro with 16 GB of RAM, but in the not-too distant past I had to make do with a lowly Mac Book laptop maxed out at 4 GB of RAM—of which the machine can really only see 3 GB—and Photoshop 13.0.5 ("CS6") still runs reasonably well on that pauper's system under Snow Leopard 10.6.8.
That Mac Book was rescued literally from the trash by yours truly after the Apple Genius Bar declared it unrepairable when in reality its only problem was a swollen battery.
I upgraded the RAM from 2 GB to the maximum as mentioned above, and attached an external 160 GB FireWire HD as a dedicated scratch disk. The importance of enough scratch space is often vastly underestimated.
All that being said, the performance of Photoshop on the 65-lb MacPro is light years ahead of the Mac Book, which is to be expected.
Intel Xeon Mac_Pro1,1 2.66 GHz Quad; 16 GB RAM; mutant/flashed, factory-overclocked 875/1225 "Apple PowerColor" ATI Radeon HD 5770 with 1 GB of GDDR5VRAM driving side-by-side dual 22" CRT monitors in Extended-Desktop mode; Mac OS X Lion 10.7.5 and Snow Leopard 10.6.8 boot drives; intrusive Spotlight and frivolous Dashboard permanently disabled; USB wireless 'n' available but connected to the Internet and networked via wired Ethernet.
Photoshop 13.0.5 has over half a TB of deicated scratch space on this system.