Just wanted to post to possibly help the next person who tries this.
As you know, much is made of the caching engine for MediaSignage. It works great when the device loses its internet connection after booting. But there are some issues when there is never an internet connection.
The mediasignage player (1.9.102 at this writing) does not do a 100% job of displaying content as you would like when it will not have an internet connection after initial registion during setup (which is required). MediaSignage has the functionality to export and import the player data, but I found this to be problematic.
Reading and watching everything I could, one would assume you could just export from the studio and import to the player and all would be fine. That was not the case this weekend. I created a campagin for a venue that I knew would not have internet access. I created a scheduled campaign with one timeline scheduled 24 hours and set the priority to low and scheduled several other timelines to play at various times throughout the day with priorities set to high. I ran the campagin and even pulled the internet cable and watched it run.
After setup at the venue, I found that regardles of the time, only the first high priority timeline would play and repeat, no matter what time it was. All other content was ignored. I tried everything, to no avail.
I hope to do a lot with mediasignage, but some of it is for venues that do not have internet access. Do not make the same mistake of setting everything up at the office, disconnect and turn it on at a venue without internet access and expect to see what you worked so hard to accomplish.
