I don't know if you went to the post or not....but, what it says there, is I tried to save it out as a "vector" format, which in PSP, all the common formats are lumped into one option (.eps, .ai, etc).
When I save that file, it asks me if I want to merge the image, based on my settings. I have no idea what settings those might be, I did a default install of the software....maybe it's in the image? I don't know. But, even when I say ok, hoping maybe it didn't merge it, it comes out as a raster flattened image.
This is version Photo X2, and the same thing happens with version 8, which the original creator has.
And, on the note of why you would want to create it in PSP, you know, I understand when you only have certain resources available to you. Most of us would never use Photoshop Elements when there is Photoshop, but for example, a mom and pop store who only want things to be simpler and more turn key, that appeals to them, and so PSP appeals to a certain demographic as well. It only causes problems in situations like this.