It's usually because the file size is to big. Might want to click on the tab that says PHOTOS on the top of your page becuase that allows for bigger file sizes. If you do that then just post the link in here. /forums/images/graemlins/blush.gif
Since you have already posted pictures in TBN PHOTOS, Just copy the URL when looking at the photos. Use the URL feature below the post box under Instant Markup. Then paste the url in to the box that shows up. I use Click Here in the Web Page box that shows up after clicking the OK box.
Here is a program that other here on TBN use for sizing their photos. pixresizer.