My b2evolution Version: 4.x

Trying to paste the Paypal "add to cart" buttons within a post on my website.

I got it to take once as you can see here:

http://www.zlogonje.com/blog5.php

But cannot get it to take another code for a different product.

This is what pops up when I hit "Publish"

    Illegal tag: form
    Illegal tag: input
    Illegal tag: select
    Illegal tag: input
    Illegal tag: input
    (Note: To get rid of the above validation warnings, you can deactivate unwanted validation rules in your Group settings.)
    Invalid content.

I've searched through the forum for other issues and they mention making a change to the parameter functions file but that fix seems to already be in the 4x version that I am using.

Any help? Any idea where I can turn off the validation rules?

Thanks!