AdvDBLookupCombobox dont list data

I'm trying to get the   AdvDBLookupCombobox to list data from a query.

I have set the property Listsource to the datasource I want listed.

I have created 3 columns and set the Listfield property to the field in the listsource datasource.

There is data in the datasource, I can list them in a grid, so it is open.

I have set the Datasource property and field also for the table from where i want the lookup.

I have looked in the samples and documents, and searched this forum without getting a hint of what I have missed.

Do somebody a hint of what I have missed. 

Thanks in advance