[otrs] Example of Ticket::CustomModule###001-CustomModule Usage

I'm planning to customize our ticket escalation criteria a bit. This sysconfig setting looks like exactly what I want. Ticket::CustomModule###001-CustomModule I'm not very fluent in Perl's style of inheritance but I have noticed that OTRS code uses the @ISA array. Therefore, I assume I only need to implement the functions I need in my module and add the base Ticket.pm to my @ISA array (so that all others will be found in the base Ticket.pm). Is this the most manageable way? I searched online for an example but didn't see one via Google or the lists. Hugh