That size in the page should not matter because your tile runs in an iframe and can not be influenced by the parent page.
Maybe your css definition is not correct. Can you post your css?
Thanks for replying.
I honestly don't think it's my CSS as I see the exact same issue on other sites that sit on Jive. My community is gated, so you can't check it out, but take a look at Welcome | Akamai Community. Akamai also uses Jivex and if you start re-sizing your browser smaller, you will see what I am talking about. I have seen this on at least 2 other sites that sit on Jivex as well.