Need Help. runaway script after upgrading

I upgraded last night from 2.08 to 2.12 everything seemd to go fine.

Today i get email from Dave at Cyberlnc that i have running some sort of captcha script thats using up all their resources.

He beleives the the SEO functions got messed up on my upgrade. The Administration is fine but front end is terrible. all links on home page get a 404 error.

Need help as im terrible at this.

Should i revert back one at a time back to 2.08 or is there something else i can do. I did like this latest version but not when my site is useless.

I just turned off the SEO addon and everything seems to be ok.

Though want to have the SEO addon active but at least site is working now.