Problem about Dragon Quest 8

[haojie_ma]

I got some problems about running DQ8 on PCSX2: my system is a Macbook Pro(Intel Core i7 2.3Ghz/4GB DDR3 RAM/GeForce 650M with 512MB VRAM), Mac OS X 10.8, and PCSX2 0.9.6. When I run DQ8, the CG animation at the beginning seems quite smooth, but when Yangus talks with Hero, some texture glitches happens(for example, the wagon is full of black and white blocks). And what's more, as soon as the first dialog ends, the screen becomes darker and it seems totally freezing. How to solve my problem?

the config:
BIOS: USA v02.20 (spch) (and my DQ8 is USA version)
GS: ZZ Ogl 0.21.213 (Interlace0/none anti-alising/640*480 and no other advanced options)