haha, yeah, I had noticed that xD
and I think I got it right now.
<img src="https://dl.dropboxusercontent.com/u/20613220/Captura.PNG" border="0">
what i need was to only count the segments between nodes, plus the segment between object and node 0
however i don't have the slightest idea why the "pick lowest" condition is picking both instances... the manual said that even if 2 instances had the same value, would pick only one anyway...