Thank you for your time and patience.
I am posting on a thread "SleepyHead on Ubuntu 16.04" because I guess that I have a software problem related to "SleepyHead" and "Ubuntu 16.04", specifically a segmentation fault. The machine I have is officially supported by SleepyHead, actually a DreamStation APAP. So, it is unlikely that the specific machine is the culprit.
I have compiled the v1.0.0-beta-1 with QT5.5.1. Now I am able to load data directly from the SD card. Till now I had first copied the SD contents to a folder, to avoid having to mess around with the card, and was trying to read from that folder. I am pretty sure that I had also tried to read directly from the SD but this was perhaps during the first tests with the version that is in the repository. Don't know exactly.
Reading data from a folder instead of the SD card still doesn't work for me. It doesn't work with the version from the repository, nor the version for Ubuntu 15.04 in the author's page, nor the windows version running on an XP virtual machine nor the version I have compiled. I have tried to point at the folder containing P-SERIES, pointing to P-SERIES itself and even to the specific serial number directory (although LAST.TXT points to it. No luck till now.
So, while my configuration is functional, I would like to find a solution for this. Is everyone else able to load data from a folder?