Now I'm trying to understand the page-layout/template relationship logic, which is far from obvious, but after much playing around, I think I'm just beginning to get somewhere...

Anyway, what I can't figure out is how to make full-height pages, irrespective of their content. On the phpwcms.de site, the height of the overall table changes from page to page, and some pages look weird - very short, whilst others are taller than the window, depending on content.
I'd like a fixed-height table, expressed as a percentage (100%) of window height, rather than a pixel-based height, which is always a compromise. This way, "short" pages will always fill the window vertically, whilst pages that are over 100% will adjust. Even if the bottom of the page is relatively empty, it doesn't matter - I still feel it's nicer that way.
I can't see how to implement this - when I use either <table height="100%"> or <td height="100%"> in either the "left" or "right" zones of the template, to "stretch" the table, it doesn't work...can anyone offer advice?