I asked for help on this over at the Yahoo list and PAul responded. I hope he can help, other than telling me that I'm doing it wrong (though that is a step in the right direction).
It seems like we can't actually do scripts for items (bear me out), it seems that we can only attach special abilities which have been scripted differently, so that if we change the "Shillelagh"special ability script to use for an item, it is changed for every other instance of "Shillelagh" in the game.
Spells, we can definitely script.
Until Tarlanon tells us how broken GPDL is, I'm going to assume that it's not broken very much - only the things listed in the various threads around the forum - and that majority of the problem with GPDL/scripts/Logic Block, is user ignorance/inexperience.
There is woefully little documentation for scripting (and GPDL functions), so until someone comes along who gets it ('cause I seem to be missing something), it seems we'll be able to use about 20% of what DC has to offer.