Missing and blank pages in my .ascm ebook in Adobe Digital Editions

Hello,

I am having some trouble with an ebook I just bought on booktopia.com.au

Some pages don't seem to be loading. It is not just blank white pages, but no page visible at all in some places, just the grey background of Adobe Digital Editions.

I found this adobe troubleshooting page which seems very promising:
Blank pages or missing images when you read digital content (Digital Editions)
yet when I follow the instructions Adobe Reader 7 is not an option to download, even though that is what this page tells me to do. As it is, I have Adobe Reader XI, but since the file I am having trouble with is an .ascm file, not a .pdf, I don't know how Adobe Reader would help at all.

I am using Windows 8.1 on a PC.

If anyone could help me get to the bottom of this, I would be very grateful.