You may find the offline version downloaded of your presentation is the standard dual screen layout, even you have set the presentation presented as any customized layout. Therefore, we are in beta a Customized Layout Offline Kit. You can download these add-on file to overwrite the offline files to gain the customized layout in your offline version, too.
You can download one of the following file and unzip to the folder where your offline files located. You can upload the files and files inside "theme" folder to your server where host own presentation with customized layout in your own server.