[otrs] OTRS Upgrade and custom code

Hello all, I have started work in a department have been using OTRS for a few years now. We are currently running OTRS 1.3.0. However, time has come to upgrade to OTRS 2.0.4 and we are worried about how this will affect the custom scripts that have been written to customise our system. Given that the upgrade docs within the source say that around 80% of the configurations have been re-named, does anyone have a simpler way of migrating the custom scripts over to the new system? Thanks in advance, Declan