[DrChiper]

The following annoying problem haunts me a long time, and yesterday I had it again so its now time to mention it.

I like to use the "Arrange into folders" function when I'm compiling books. I use the following settings (see first Thumnail) to accomplish this.
Very often, this however results into a sub-folder (many times just only the images folder) to start with a lower-case character instead of the required upper-case character (see 1st image).
During editing the ebook, you will not notice this as everything seems to be OK.
However, after saving and using the ebook, the images will (obviously) not show up.
Inspecting the ebook via the editor now clearly show a question mark before the not found image and the "Check book" function indicates an appropriate error message (see Thumbnails 2 and 3).

The problem can easily be corrected by opening the ebook via for instance 7zip, and replacing the sub-folder name to start with the proper upper-case character.

That said, I never ever found out why this happens. I used to thought that it is because the ebook already contained a sub-folder name "image", which starts with lower-case. But it also happens with ebooks which had previously no sub-folders at all until I added them.

Is there somebody who can shed a light on this mystery?