asiaexpat wrote:thanks for all your help
I don't think i want to create a sitemap as much as I want to create a sitemap xml file to submit to Google--or do I have to apply the whole sitemap mod??
Well, the mx Google sitemap module will do it all for you, everything is auto, you'll just have to submit once on file to Google once installed. It is very powerful to have Google spider your site well.
There is no way nor no point to install it partly, but, you'll find it's very easy to install, not a single change to phpBB files nor DB

That's where we come to point two :
asiaexpat wrote:I am also concerned as phpbb3 is coming and the more mods i apply the harder it will be to migrate
mx
Google sitemaps, as well as
mx Sitemapsare module not mods, meaning, they do not change anything to phpBB, migrating won't be of any more problem than to update the mod, eventually (again, updates on those will basically be overwriting files).
As those two are really powerful as an Search Engine Optimization enhancement, I recommend you install both. Take your time, SEO is not a matter of one day, take a look to the demos.