I have had a recurring problem with the transcription failing when there is a double page where one page (usually the first) does not contain writing. See picture nr. 1.
And another example. In image nr. 2, the transcription fails. In image nr. 1, I have cropped out the first “page” (or half-page) which contains little actual writing. I am beginning to suspect that this problem is related to Leo’s troubles with pages containing marginalia.
And a final example. Leo fails to transcribe image nr. 1, where the first page is more or less empty. After cropping out the empty page, the transcription is successfull. On the next page, the situation is reversed: the first page contains writing, while the second is empty. Here, Leo has no problem with the transcription. It thus seems to struggle when the first page is empty.