Hello Caperguy and welcome to the forum!
I've heard that Krylon stuff can be pretty good. I've only ever used it once on a plastic aircraft model and it worked out nicely. As for the flat and dull appearance, I can only speculate that particular color is supposed to dry to a flat and dull, non-shiny appearance. Check the cap. Sometimes a gloss cap will indicate a gloss finish, a flat cap will indicate a flat finish, etc.
I see on the Krylon web site that their Fusion line comes in gloss, satin and flat finishes. It's possible you may have grabbed the flat finish by mistake.
Just out of curiosity, which color did you use? You might be able to salvage your work yet. I know you said there's no hobby shop where you live but is there a craft store of any kind? It wouldn't have to be a model shop, per se, but even if there's a train shop or a Michaels or even a Walmart, they might have some clear gloss sprays you can use to apply a gloss finish.
I know some people swear by Future floor wax as a gloss coat. I, myself, have never used it as a gloss coat but I have seen lots of pictures where people have gotten phenomenal results with it. I dip my clear parts in it and it works great. People hand-brush the Future on and it levels quite nicely.
I hope this helps,
Eric