Hello, First time using this forum. I am website developer/hosting comapny working on a project for a client (using zencart for the first time). I successfully installed google checkout a couple months ago. CLient then switched to "free shipping" with orders over $5 and now google checkout option greyed out and gives the following error. Not sure where to go to fix the problem.

Not available for these items
What is Google Checkout?
* There are multiple shipping options selected and they use different shipping tax tables or some dont use tax tables

Would appreciate any help here.