I have been running some tests like this on my end and can confirm that the PG code and CSS Menu Writer code are not incompatible on their own. Do you have a link to a working PG page and one with the menu on it so that we can examine them? If we can see what is being rendered and what is not it may help us to understand the problem. Also, do you have error reporting turned on? If not you should enable this so that you can confirm no errors are occurring.