Sorry to hear you're having problems. I think a little more information will be needed to really help you solve this problem quickly. If you don't mind, can you post some code samples (using the forum's "Format Code" tool) showing your Grid configuraiton and your relevant code-behind code? That should help us quickly recreate you scenario and provide some suggestions.
In the mean time, I'd also suggest checking your NET traffic with a tool like Firebug. When your page loads, look for any errors (like 500 Server Errors, or 404 HTTP Errors) related to the grid images. Those errors will further help us understand what may be happening.
Finally, as I'm sure you're aware (so for others reference), there is an online demo showing integration between RadGrid, the BinaryImageColumn, and RadUpload, available here:
It may provide additional guidance by example.
Hope that helps. Looking forward to your details.