There could be a couple of reasons for you not seeing it.
1.We have updated the pictures so you might need to clear your cache and reload the site
2. There are three different banners. 1. for the main website and 2 different banners for the TGTT theme and the TGTT Narrow theme as pic sizes are different.
As for including more pictures, if we get more pictures we can use them. The problem is that people post up tiny low quality pictures (320 X 200 etc) and expect that they will fill a 1120 X 150 space. Unfortunately we can only work with the pictures we get so if you post camera phone shots of your car or general rubbish photos dont expect to see them in the banner. If you post good, high quality and large photos in the thread I started a while back then your car will be added - again just so people understand... if the picture is tiny or crap quality or just a bad picture then it cannot be used.