Want to upgrade but kind of afraid, a few questions please.
 

One of our forums has a cpl million post and 60,000 members. My host is upgrading my sql and php as we speak to handle the upgrade from 3.7 to the new 4.0.

My concerns are, my forum now is in /forums and I use Vbadvanced in the root. Will an upgrade to your cms just overwrite the VBA cms? Will it be difficult to replace with yours? If so can I pay you to install it?

Another concern is we get quite a bit of traffic to our front page from the search engines now. maybe a thousand or more hits a day. Is your CMS SE friendly as far as title tags and such?

Our members really like having the recent threads on the front page along with poll results and such. Can I do this with your CMS?

Our forum is five years old now and I installed a few things on it I probably shouldnt have like FlashChat and such. I dont care about losing the chat and such for the upgrade I will replace them later but my question is will these things hamper the upgrade?

Also I looked but couldnt find what kind of payment processers can we use on the new forum and is there a banner rotation script built into the forum?

Thanks for your help I look forward to upgrading.