I discovered a new bug in the latest version of this plugin (1.5.0). With that version installed, the front page seems to use the DigitalSignagePressTheme instead of the activated theme when the front page setting is set to show latest posts. When the front page is set to a static page, this bug is not there, not even on the posts page. I was able to reproduce this bug in PHP 7.0 and 7.1 using WordPress 4.8.2. I also tested the last version of the plugin (1.4.7) and this bug was not in that version.
(If you noticed my post in my last thread, it turns out that my test bench and my production server had different settings under Settings -> Reading -> Front Page Displays which is why I thought the bug was only on one machine. Turns out the bug depends on the setting, not the PHP version.)
I’m less concerned about this bug because I plan to use a static page for my application, so no big deal. I just thought I would try to help you out tracking it down.