On further testing of my new module I've discovered that for anonymous users strange values are being displayed in the generated block. I've determined that this is due to block cache. I turned it off on my production version and it seems to be functioning correctly. I did not have this issue on my development box.

As with my earlier problem with css for anonymous users, I would appreciate any thoughts on how I might deal with this. The vast majority of visitors to this site are going to be anonymous.

Thanks