Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See Parameter IDs.
Parameter: Preview for New Nodes
PREF_NODE_EDITOR_PREVIEWParameter: Grid
PREF_NODE_EDITOR_GRIDParameter: Navigator
PREF_NODE_EDITOR_NAVIGATORParameter: Info
PREF_NODE_EDITOR_INFOParameter: IDs
PREF_NODE_EDITOR_IDSParameter: No Value
PREF_NODE_EDITOR_HEATMAP_NOVALUE_COLORParameter: Gradient
PREF_NODE_EDITOR_HEATMAP_GRADIENT