We've created this Forum Thread with some workarounds and advice to assist you in publishing you ebook.
cover of Spiffies and Loonies, volumes 1 & 2
Last year I made two separate editions, one in English, the other in French, of my bilingual sitcom in two volumes Extrapolations. To avoid confusions, the title of the English version is Spiffies and Loonies, while that of the French one is Fringues et Dingues. Each was in two volumes.
Now, while the original bilingual edition is left as it is, I think it preferable to make a single volume of the two of each of the monolingual editions.
Here is the front cover of the English one. Do you like it?