On my Treo I could browse a set of saved-off web pages stored on the SD card. When I try it on the Pre, it says "Cannot display local files". Why not?

In fact, with no network access, when I try to view a local page it says "The network is currently not available. Please enable networking before using the browser." That's the main reason you save off web pages, so you CAN view them when you don't have network access!