Just reporting what looks like a small hitch or oversight.
qtVLM ouputs
   <wpt lat="43.272917" lon="16.518167">
      <name>HR_Brac_Uvala_Blaca</name>
      <desc>NNW to enter<desc>
   </wpt>
while the correct one should be 
   <wpt lat="43.272917" lon="16.518167">
      <name>HR_Brac_Uvala_Blaca</name>
      <desc>NNW to enter</desc>
   </wpt>
see <desc> closing tag instead of </desc>.
openCPN does not log the error and fails to import any mark.