[jusmee]

After a lot of trial and error, I found the problem. It's not spaces, but other characters, like commas and ampersands, that stop it working if they are present in the filename. I think it's because Coolreader stores the info info in XML in a .cr3hist file, and the funny characters upset the XML.

Now I wouldn't normally use characters like this in a filename, but some sites like Baen publishing, do! So beware. They also use single and double quotes, and even exclamation marks - don't know how many of them will cause you to lose you place and your bookmarks either (it doesn't warn you when you start reading the book, so you only find out the next time you open it).

Just an aside, Coolreader's choice of putting all bookmarks in a single file is a bit inconvenient. If nothing else, it means you could lose everything at once, and you can't move your bookmarks with your book to another computer.