_page feature base layers

Here's a tip I learned the hard way! I am building a complete site in one psd using the _page feature. I kept uploading and checking the generated pages as I built each page and everything was okay until I tried the last time. Only the last couple of pages I built were showing up. The other html pages were there, but they didn't have any of the content. After a bit of head scratching, and resorting to RTFM, I discovered my error. On the next to the last page I adjusted the size of my _page layer which blew all the page layers above it! Like it says here in the documentation, "These '_page' layers should be the same size and fit right over the top of one another - only one will be visible at a time." This is very important!