Collisions and warning message

[Daniel Tonda Castillo]

Greetings to all:

I get a warning when compiling a piece of music:

Ignoring grob for slur. avoid-slur not set? What does this mean?

I shortened the example and also found out that there are a bunch of 
collisions that appear when using fingerings and string numbers.

Just for the purpose of making the collision appear on purpose, I added 
a fingering and changed the "a" to <aes'\3-2-\RH #"i">8. The flat and 
the fingering clash. I know that I could use some padding, but shouldn't 
this be managed by the NoteCollision stuff?

¿Maybe you can test it and see if it's a bug or a mistake on my part?

%% BEGIN

\version "2.11.5"

snu = { \set stringNumberOrientations = #'(up) }
snd = { \set stringNumberOrientations = #'(down) }

#(define RH rightHandFinger )

\context Staff  <<
 \time 2/4
 \clef "G_8"
 <<
   \context Voice  \relative c {
     \voiceOne
     \stemUp
     \set fingeringOrientations = #'(left)
     \set strokeFingerOrientations = #'(up)

     \snu <aes'\3-2-\RH #"i">8 %% The flat is to demonstrate the collision
     \( <b\3-3-\RH #"m">  <c\3-4-\RH #"i">  <d\2-2-\RH #"m"> |

     <e\2-4-\RH #"a">4 <e>4 \)
   }
 >>
 <<
   \new Voice \relative c {
     \voiceTwo
     \stemDown
     \set fingeringOrientations = #'(left)
     \set strokeFingerOrientations = #'(down)
     <a-0-\RH #"p">2
     <a>2
   }
 >>
>>

%% END

When I remove the string number directions and the fingering directions 
I also get clashes. I attach the png output also.

Daniel Tonda C.

daniel.tonda.vcf
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