Actionscript 3 :: Defining An XML Format For A 2D Array (Grid) Of Items

I need to define an XML format and then read it in ActionScript3, which will be storing:the number of rows and columns in a grid the horizontal and vertical spacing in pixels the size of each square in the grid in pixels an optional label for each square in the grid an optional hyperlink for each square in the grd.The following is the kind of thing that would meet my needs at the moment, which demonstrates the four square types:[code]

My questions are things akin to "Should there be units on the spacing and size? (like 10px or 300px)" and "How bad would it be to use a XHTML subset of (table, td, tr with a elements in each cell)."But really I'm fishing for any precedent, ideas, or best practices. Particularly as they are relevant to processing such a file in ActionScript3. The goal is to be able to read the grid properties and to define a function that will give back a square's label and url given a row and column. (The easy thing about this format is that getting a square is just a matter of indexing into children of the grid node by integer... first column, then row.)