If you have created a new layout Page or Collection in the Layout section and it is not playing on screen, you need to check that the Layout has been assigned to your Channel.
Layouts Pages and Collections are required to be assigned to a Channel so that content you have added to a Playlist can play in the designated areas of the designed Page. The Channel Content asset in the Asset section in Layouts is required by default when creating a new Page.
Channel content that does not have a Layout or Collection assigned will play full screen and not within the Channel content zoned area you added as part of the Layout design process.
To assign your Layout Page or Collection to a Channel, please check out the help article here
If you can still not able to get your Layout to play, contact support@digitalsignage.net