I am using SBO2005
I have creaded A UDO form and added CFL to one of the edit-text.
When I Press the TAB key, or enter a wrong value in that edit-text, the CFL appears, but, when I choose an item from the CFL, the form is closed and there is no value in the corresponding edit text
Once it opens, you need an item event to get the value and then display it in your text box. Just making a datasource is not enough. Look at the example that comes with sdk 2005 go to c:\Program files\SAP\SAP Business One sdk\Samples\COM UI\VB.NET. The example is "17.ChooseFromList". In this example you'll see there is an item event that triggers off and gets the value.
Hope this helps