> I guess the tickets bear a wrong CustomerID. Check that. Work on the 'Map' in $Self->{CustomerUser}.

Sounds reasonable anough but the CustomerID (for the customer user and the tickets in question) seems to be alright (I see the tickets in the Ticket Overview screen allright). But maybe the link between ticket and article is the problem? unfortunately I am not quite able to verify how permissions verifies to articles.
 
Stig