Sorry if what I said was confusing. In the desktop IDE where you create the game, you can drag passage blocks onto each other and they will stack. A number will appear in the corner showing how many passages are in the stack. When you click a stack, a box will pop up so you can select one passage, or ungroup them.
Regarding the "book cover" type image: I got to experiment last night and was able to get a picture in the sidebar area which is very nice. Haven't tried, but I guess you can change it within a passage so there can be some atmosphere art for different areas, or it can be a persistent logo for the game.
I noticed in the user manual (done with AXMA) it seems like you get the Title/Subtitle/Author pop up, then there's a big AXMA logo that pops out. Is that a separate function, or is it just a passage displayed with the [[*passage]] that contains that picture somehow?
The pop-over windows are very nice. You just use an asterisk (*) before the link to a passage, such as [[*Look at the house]] the same way you'd use a + to add a passage to another without clearing the screen. A click on nothing will dismiss it and return to the main text, or if there are links within the popup, the player can select them.