Looking at your site how sure are you that you need 70,000 pages?

For the sitemap I would stop trying to use a website and do it yourself. It looks like you are running IIS. They have a sitemap generator that you can install on a server easily and run it there. It looks like you have GoDaddy, they catch a lot of crap but I have always found their technical support to be top notch. If you can't figure out how to do it on the server I would give them a call.