Excel Macro compatibility bug in LO 4?

I have an Excel macro which uses a form to input data. The form uses combo boxes to select values from a range on a sheet in the workbook. This works fine in LO but on upgrade to LO 4 (ubuntu 13.04) the combo boxes just show blank. All other features still work.
I suspect this is a bug. Anybody else had problems?

When you say “Excel macro” do you mean it is written in VBA script? VBA script and LO Basic are two different languages and largely not compatible. You would generally need to re-write any VBA macro as a Basic macro.