I have also encounter such issue but solve:
1. Using other's computer to browser the text-only page.
2. right click the page, and LOOK AT THE SOURCE HTML CODE.
3. Watch out the part that show the image. The important point is, what is the path of this image?
90% of this problem is caused by incorrect path, which is caused by incorrect setting of your website.
For example, when I use Mambo (It's joomla now), and have other people access my website, they can only see the text but no image. After digging into the issue I found that in Mambo there is a variable :
$MOS_live_site = "http://localhost/mambo"
This variable make all path, including images, to:
Which, in my case, is of course not the right path.
So I reconfig this variable to :
Then problem solved.
So the important thing is: look at the source HTML code and see what is the path of your images are being pointed to.
Hope it helps.