i started a clean #237, and tried both drag&dropping and choosing the template file.
exe and tpl were kept in different folders. tpl is rawr 0.1.1
both methods worked for me.
since you say HFS doesn't even use the new template, you are doing something wrong, or you found a way to reproduce a bug, but "change my template file" is something i just tested.
in case, i can watch you doing it, so to understand more.