The missing texture issues seen in #114 and #124 appear to be caused by using the second "Create NEW Book" item. This is the one with the "enchiridion" identifying NBT tag. Using the identified book will create a new book that generates with no texture. However, if you use the non-NBT item, the intended effect of a book with the default book texture will occur. Please look into this as soon as is convenient.

Scratch that, it appears that the texture only loads correctly in the session the book was created.

Newly made books won't load the texture until you reboot minecraft.
Unless that's been changed.