The Apocalypse Door

From Author Wars - https://authorwars.com/publications/the-apocalypse-door-483999.html

Overview:

Title: The Apocalypse Door
Author: James D. Macdonald
Year: 2009
ISBN-10: 9781466838451
Publisher: Tor
Price: $7.99
Pages:
Binding: ebook
Type: Novel
Title Reference: The Apocalypse Door
Notes: First edition. Amazon Kindle's page count 224. Data from Amazon.com as of 2014-10-07. Price from Barnes & Noble as of 2014-02-11.
Cover has (hard to see) signature and the art appears in Dreamlands