Whenever I need to do a spotlight I use the Effects->Illumination Effects->Lights tool, you can remove all but one of the lights then move it into position, adjust the width, length and brightness of it in relation to the background, if you greyscaled you're texture before then this can be used to make a spotlight with the aztec underneath preserved.
Edit: I use Paint Shop Pro 7, it screwed up the selection tool but everything else works like a dream, except registries, corel draw is much better for that.