More fun with Word docx files

I've been updating a file that I create in word and send to guests in pdf format. Last year I added a mobi format due to the astounding Calibre.

This year I'm adding an epub, but it's looking a bit odd.

Here's the original file:

https://drive.google.com/file/d/0B68...ew?usp=sharing

And here's the mobi, which I think is pretty good:

https://drive.google.com/file/d/0B68...ew?usp=sharing

But there's the slightly sad looking epub:

https://drive.google.com/file/d/0B68...ew?usp=sharing

I think it's the docx headers that are causing the problem. There's our logo in there and that seemes to be cropping up extra large all over the shop.

Here's the conversion log:

https://drive.google.com/file/d/0B68...ew?usp=sharing

Any advice most appreciated.