Username or EmailPassword
I'm not certain if there is a way to get around what you are asking other than right clicking on the image or couple of images that are missing and select "Reload Image." Doing this is not ideal however it would keep you from having to download them all again, especially since you are on dial up. However I'll dig around when I have time and see what I can find out.
If this option cannot be found or set, you might consider emailing the good folks at Opera about it. I'm sure that option would be easy to add and they have always been very receptive to user suggestions.
Regarding the eyeball looking icon I mentioned... it is one of Opera's default icons normally to the right of the search string. What it does is toggle the menu bar that shows "Find in page", "Voice", "Author mode", "Show images", and "Fit to window width" on and off.