Hi Toni,
DOORS client customization is carried out mostly using DXL scripting. You may find simple examples like this one or very sophisticated ones like Requirements Management Framework which can provide a very high level of customization. Actually, the latter is a product itself requiring an additional license.
There are many resources to learn DXL. Check out this search.
Layout customization, however, is not the main target of DXL scripting. Without any programming, little else can be done beyond the typical 'Options' menu in the tool itself.
Regards
Oskar
#Engineering#Sustainability