My test, performed on TYPO3 CMS 6.2.10:
1) uploaded
photo_01.png
photo_02.png
photo_03.png
photo_04.png
photo_05.png
in /fileadmin/Images/ using FileList Module
2) created 5 CE images in a page, each with one image; for each I used "add Image" because they already were in /fileadmin/Images
please take note that inspecting the HTML source in the FE, the images path are either the original /fileadmin/images or /fileadmin/_processed_ if some processing took place (e.g. scaling for exceeded maximum width)
3) I created 2 other images: photo_01.png and photo_02.png to replace the corresponding images previously uploaded.
3) edit the first CE inserted in the page > Images Tab > "Select and Upload File" > I selected "photo_01.png" > Javascript Alert: "Shall the existing file be overwritten?" > It does not matter what I answer at this point, because the file will be uploaded into /fileadmin/user_uploads or in the processed folder with a random generated name
4) I uploaded photo_02.png in filelist module > Javascript Alert: "Shall the existing file be overwritten?" > If I answer "OK" the original file is overwritten, and in FE the file has changed (even if it has been processed)
NOTE: if I answer "cancel" the file is not uploaded at all! (No unique filename available in "/Images/"!Upload of file "photo_03.jpg" failed!)
5) Again, edit the first CE inserted in the page > Images Tab > "Select and Upload File" > I selected ANOTHER "photo_01.png" > Javascript Alert: "Shall the existing file be overwritten?" > Answering yes, the file uploaded at point 3) is actually replaced, but there is a problem: the list (IRRE list, right?) of the images shows it amongst the existing files, so it seems there are THREE different "photo_01.png" related to the CE; to load the correct list, simply save the element,exit and edit again.
So, the problem is: the IRRE is not updated.
I think there are also some strange behaviors of the processed files, but I must investigate further
Is this test exhaustive,or am I forgetting something?