Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See Parameter IDs.
Parameter: Use Transfer
POLYGONSELECTIONTAG_ENABLEFIELDSParameter: Transfer Mode
POLYGONSELECTIONTAG_TRANSFER_MODEParameter: Update
POLYGONSELECTIONTAG_UPDATEParameter: Select&$Shift to add
Ctrl to remove from selection
POLYGONSELECTIONTAG_COMMAND1Parameter: Deselect
POLYGONSELECTIONTAG_COMMAND4Parameter: Hide
POLYGONSELECTIONTAG_COMMAND5Parameter: Show
POLYGONSELECTIONTAG_COMMAND6Parameter: Solo
POLYGONSELECTIONTAG_COMMAND2Parameter: Show All
POLYGONSELECTIONTAG_UNHIDEALLParameter: Tolerance
POLYGONSELECTIONTAG_FIELDTOLERANCEParameter: Use Deformed Points
POLYGONSELECTIONTAG_DEFORMEDSTATEParameter: Fields
POLYGONSELECTIONTAG_FIELDS