Thanks for the help. The google group will help us to start the development quickly. I would prefer to use the public release as much as I can, so that we are always up-to-date in the tape-out run. Currently, we plan to use the commercial tools where we have very familiar with, and try to deliver a GDSII as soon as possible. Later down the road, I believe we will start remove these dependency and move to open-source tools. At that time, we just need to use the publically available resources.