Problem with thumbnail view in ThreePanes layout (4,7,16,0)

Due to the the security update from Microsoft (KB953839) our ActiveX Image Uploader didn't work anymore. We developed an application using the ThreePanes layout with version 4,1,60,0 of Image Uploader. After reading on your forum about this problem i upgraded to version 4,7,16,0 (with new CLSID's) and now the explorer part of the Image Uploader works again. I can see files on my file system, select them to be transported to the third pane, switch them over to the third pane, but there the thumbnail preview of the images won't show. It tries to load the image thumbnail for a little while and then in stead of the thumbnail displaying i get the error message :

"Image Uploader ActiveX control is necessary to upload your files quickly and easily. You will be able to select multiple images in user-friendly interface instead of clumsy input fields with Browse button. Installation will take up to few minutes, please be patient. To install Image Uploader, please click on Information Bar. After page reloading select "Yes" when you will see control installation dialog"

This message is the same as i had before (related to the Microsoft update) but at that time i didn't see any part of the Image Uploader component at all. So the problem is that after the upgrade to 4,7,16,0 i do see the Explorer part of Image Uploader (which suggests to me that the new version was implemented succesfully) but i can't get it to work on the thumbnail view in the third (custom) pane of the ThreePane layout. I manually deleted all old entry's from Image Uploader from my downloaded program files before installing the new one (installed succesfully) but nothing seesm to help. I'm also using the new iuembed.js that came with the 4,7,16,0 version with all the new CLSID's.

Do you have any pointers as to what i could be missing as i'm out of clue's at the moment.