This error occurs when control is drawn in cache for animation effect (SkinManager.AnimEffects.FormShow.Active is True).
Standard FileListBox haven't checking of available items in DrawItem procedure : TextOut(Rect.Left + offset, Rect.Top, Items[Index]) < Index is 0 here, but Items not exists.
I can suggest two solutions :
– add a skinning support for this control (SkinManager.ThirdParty property)
– change SkinManager.AnimEffects.FormShow.Active property to False