The current version of Kenja has some problems in publishing very complicated rooms with several layers of content. The first time you publish the parent room, some of the tiles and files in subsequent sub rooms may not appear in the published site.
If this occurs, simply select "Publish Room" again, and click on "Content" in the pop up browser. Finally, select "Check and uncheck all" (see screenshot below).
By repeating this process a few times, all the content in the room should be published - you can check this by selecting the "+" button on the pop up browser depicted above.