Last night I try to update to Ten3 V3 SW which works very well. First, download the V3 from this link http://www.smartdevices.com.cn/support/download/T15/. Then download package which fix the font and wifi icons issue http://bbs.zhiqi.com.cn/thread-48118-1-1.html. Third, download Google application from CM7 http://cmw.22aaf3.com/gapps/gapps-gb-20110828-signed.zip. This package will fix the google calendar synchronize issue. The root zip for V2 could also be used for V3.
First flash the V3 SW, then flash the package 2 which fix the font and wifi icons, then flash the google application package. Finally flash root if you want.
After update, the Google calendar could synchronize with server, the iptable and tun kernel module could be loaded. But pptp/l2tp still don't work.