Hi Marc
I've managed to work around the problem by grabbing the value on the way in and explicitly setting it after I've called the SPComplexToSimpleDrowdown function. I also noticed that if you don't change the value during the edit session then SharePoint doesn't save the value that you set explicitly (in IE anyway). I've worked around that by calling a trigger("change") function on the lookup column in question so that it manually calls the change event. That seems to have sorted it out.
But to answer the question the SPComplexToSimpleDrowdown function is called inside the document ready and after I've filtered the lookup with SPFilterDropdown.
Des Owen
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