If I create an SkinManager normally on the MainForm, all components will be skinned well. But If I create an SkinManager dynamically not in a DFM, the components of the ThirdPartyList won't be skinned.
I think the SkinManager ignores then the ThirdPartyList.
Try to call LoadThirdNames(sm : TsSkinManager; Overwrite : boolean = False) procedure after ThirdPartyList filling. Internal data will be updated in this case and maybe it helps in your problem. If not – please write again and demo program will be very useful.