For a map like that I'd tend to divide it up into a power of 2 (ie 8 rows and 8 columns) since that's more consistent for game art usage. 10 is a rather odd number to divide a 256x256 map by, for example. It's not a huge deal, but I think I'd get more use of a map that goes to 8 or 16.
Has anyone with windows 8(.1) tried using the SourceFilmMaker plugin for maya? It worked fine for me on Windows 7, but it's not working with Windows 8. Is there a way to manually set it up?