Matt
Simple Answer: You cannot use Dexterity to modify a 3rd party form. You can use Modifier and VBA.
You can create a Dexterity Customisation which uses a parallel window or triggers to change the behaviour of the window, but there is nothing in the Dexterity architecture to support an alternate version of a 3rd party window.
The reason you are seeing [NOT FOUND] and "String Missing" messages, is that you have opened an extracted dictionary. This only contains the changes and additions to the core DYNAMICS.DIC for Project. All the core resources (with an ID < 22,000) are not present and so the messages.
You will need to create a combined dictionary with a copy of DYNAMICS.DIC to see the dictionary without errors, however you still will not have access to the source code.
I suggest you look at the Integrating with 3rd Party Dictionaries and Pushing the Limits with Dexterity conference materials on the Training page of
Look at the materials above or at this KB for how to create a combined dictionary.
David Musgrave [MSFT]
Escalation Engineer - Microsoft Dynamics GP
Microsoft Dynamics Support - Asia Pacific
Microsoft Dynamics (formerly Microsoft Business Solutions)
mailto

avid.Musgrave@online.microsoft.com
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