According to the brief bit in the Sigil Guidelines (the online HTML HELP), you are "supposed" to be able to create or imbed thumbnails using a ZOOM feature associated with the INSERT IMAGE function. However, I cannot find that on-screen. Now, I am (admittedly) trying edit an existing file with images already inserted. I really don't want to have to start from scratch, i.e. delete all the images and then re-insert them. Can anyone tell me how to create thumbnails and/or insert pre-made ones? If there's an online tutorial for this, please just point me in the right direction and I'll do the rest. FYI, I'm making children's picture books for EPUB and having a devil of a time figuring out Sigil's image output (size, resolution, etc.). So any information on dealing with inserted images in Sigil would be most appreciated.