This is a tutorial I created and posted at GIMPtalk.com some time ago. In it, I will show you how to create an animated border highlight using the GIMP GAP plugin. GAP does not come with GIMP automatically, so you'll have to go to your favorite GIMP download site and make sure you download/install it. You don't put it in the GIMP plugins folder. Just save it to your desktop and double-click the installer. Sorry Mac users, this isn't for you. There is no GAP plugin for MAC.
GAP can be rather tricky at times and isn't the most user-friendly. But, I've re-written this one and tried to make it as easy as possible. Lots of screenshots and, in the typical fencepost fashion, lots of very detailed instructions. Probably too much information for you GIMP experts out there!
I hope you enjoy it and learn a new trick or two. It's in html format so just click the Download to Desktop button, double-click the zip file and save the file folder and html file to a convenient location. Double-click the html file to view at your leisure.
As always, comments and questions are welcome. If you need clarification on something, don't hesitate to ask. Just keep in mind, it may take me a little bit to get back with you.