Extract PDF or EPUB from ACSM file

Install libgourou in nix-shell.

nix-shell -p libgourou

Register the device with Adobe username and password.

adept_activate -u user -p password

Download the ACSM file. Make sure the ACSM file is in the current working directory.

acsmdownloader -f Dragon_Age_The_Missing_1.acsm

The downloaded file requires a password to open. Remove the DRM from the files.

find . type -f -name "Dragon_Age_The_Missing*.pdf" -exec adept_remove {} \;