Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See Parameter IDs.
Parameter: Language
PREF_INTERFACE_LANGUAGEParameter: Scheme
PREF_INTERFACE_SCHEMEParameter: Highlight Features
PREF_INTERFACE_NEWFEATUREHIGHLIGHTParameter: Fading
PREF_INTERFACE_NEWFEATUREHIGHLIGHT_FADEParameter: Reset Highlights
PREF_INTERFACE_NEWFEATUREHIGHLIGHT_RESETParameter: GUI Font
PREF_INTERFACE_FONTSTDParameter: Monospaced Font
PREF_INTERFACE_FONTMONOParameter: Big Font
PREF_INTERFACE_FONTBIGParameter: Show Mac Menu Bar
PREF_INTERFACE_MACMENUParameter: Icons in Menu
PREF_INTERFACE_MENUICONSParameter: Shortcuts in Menu
PREF_INTERFACE_MENUSCUTParameter: Show Undo Buttons
PREF_INTERFACE_SHOWUNDOBUTTONSParameter: Bubble Help
PREF_INTERFACE_BUBBLEParameter: Online Content
PREF_INTERFACE_ONLINEHELPParameter: External Browser
PREF_INTERFACE_EXTERNALHELPParameter: Field Remapping Graph
PREF_INTERFACE_HIDEFIELDGRAPHParameter: Simple UI for Fields
PREF_INTERFACE_SIMPLEFIELDUIParameter: Create Objects at View Center
PREF_INTERFACE_CENTEROBJECTParameter: Insert Objects at
PREF_INTERFACE_INSERTATParameter: Paste Objects at
PREF_INTERFACE_PASTEATParameter: AM Selection Limit
PREF_INTERFACE_AMLIMITParameter: AM Selection Limit (Nodes)
PREF_INTERFACE_AMLIMIT_NODESParameter: Script Word Wrap
PREF_INTERFACE_SCRIPTWORDWRAP