about SMIL

Dear all,
I am a Doctorate Student at USTHB(Algeria). I work  on automatic diagnosis
of SMIL multimedia documents. I would like first to identify which kind of
diagnosis would be really helpful for the designer of multimedia documents
and after that to experiment some technics of formal verification of
programs on SMIL documents.
Concerning the first step of my work, it is really important for me to know
the real needs of multimedia designers.
We only focus in this work on diagnosis that are linked with the temporal
behavior of the document and that are meaningful whatever the document is.
please, could you indicate me the situations of incoherences capable to
occur in a SMIL document.
Great thanks for your help,

-- 
Samia BOUYAKOUB