First of all, free feel to throw any advices in the wind, if you have a better solution !

 

• Make sure your text & HTML tools height matches that of the text (otherwise scrollbars show up !). It is wise to make them even a little bit longer, just to be safe.
• Look at the KC template exposition for a demo.
• Follow a good example: this or that. 
• Only use standard fonts like Arial, Georgia, Times New Roman etc... RC only supports a small set.
• Set the default backgroundcolor of text and HTML tools to white (double click the tool in the toolbar, go to style tab > background color.)
• If you use an external text editor, do not style your text beyond paragraphs, bold etc... style it after it is imported to the RC.
• Try to keep one page per chapter, pages should not become very long.
• Always annotate your video's or audio tools (for example with an extra text tool or HTML tool.)
• Keep enough whitespace between tools, at least 50 pixels (see rulers around the editor)
• Total content not wider than 1280px (see rulers on the side of the canvas), unless you have good reason.
• If you have a lot of examples, media etc... it can be worth trying a multiple colom structure, which is slightly easier to change content & text if needed.
• Wait with making a Table of Contents until your exposition is really nearing completion, this way you do not waste time correcting links etc..
• Use wherever possible, picture tools instead of pdf 
• Do not use background colors if it doesn't imply a semantic meaning.