so, in October I downloaded the Premiere Elements 11 trial version and I made an entire 1-hour movie with it. After the first 30 days I purchased Premiere Elements 11, filled in the serial number and the watermarks went away. All very well.
Now, a couple of months later, I opened the same project to add subtitles to it. And all of the sudden, the watermarks are back on the rendered parts of the movie. Now I read somewhere that to remove them, you have to remove the rendered files and re-render the whole thing, but I refuse to do that since 75% of my movie is rendered and I spent like 5 weeks working on it. Besides that, the watermarks were gone before. So why in heaven's name are they back right now and how do I get rid of them?
Welcome to the forum.
I have never read of a full-paid version of PrE reverting to "trial." [That has happened with some version of PrPro, but not usually with PrE.]
The Render files are JUST for smoothest playback, so before you go to output via Share/Publish, you can safely Delete the Render Files from the Scratch Disks>Media Cache. There will be nothing lost, with the Deletion of those files, to clear up the watermark, at that time. The files in the Timeline will be Transcoded separately from those Render Files, when you go to output.
The FAQ Entry on working with Projects, that started in the trial, is here: http://forums.adobe.com/message/1966673#1966673