filter strategies by customer language, by reference field in invoice form and by invoice amount

Hi,

I defined strategies based on due date scoring engine : a stratgie for score 100 (average du date < 0), score 90 (0<average du date < 30), score 80 (30<average du date < 60), ...

But I want to define strategies for special cases :

 I want to send different dunning letter model based on customer language,

I want to create different strategies when reference field contain value X or Y

I want to create different strategies by amount range

language issue is different than other issues, is'nt it ?

we can use 'filter segments!' or 'filter engine!' ? How ?

Thank you for your help

Mehdi Trabelsi