Yes I did. I only came across you today, via the article you reference, but it didn't seem to directly address my issue, except for solution 5, which didn't really tell me how to "add the artistic border"; that discussion usually leads to PhotoShop, much too expensive and complex for my needs. I am trying to help out my sister, who is only a small step away from being computer-illiterate; Mpix has sizes that would work for printing the photo, but sis wants to fill the width of an existing 8x10 frame. That led me to the idea of using borders as you suggest, but I couldn't find a way to do it without PhotoShop. Anyway, as I got into the issue (adding uneven borders), I find I'd like an answer for myself as well.
I see now that I can probably download a trial version of PhotoShop to avoid buying it, but I'm certain the learning curve would be steep, even just to accomplish the border task (I can't even handle the simpler tools I already have).
I'm looking for a way to create a frame in the LxW ratio I desire, and place a photo where I want it inside that frame.
BTW, the need for fitting the photo into a larger border was brought on by a similar dilemma, where I was trying to add a border on another photo she wanted to have Mpix print on a raised canvas frame; MPIX wraps the edges of the photo around the sides of the frame, which would have cut off people's toes. I was able to find a way to add a border using layers in Paint.net (but it was a uniform width border all around the photo, with no way to change the centering of the photo, so would work for the canvas frame and not for the 8x10 frame issue because it would only make the photo smaller, not change the proportions)
Thanks,
Wayne