Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See Parameter IDs.
Parameter: Depth
MGTEXTOBJECT_SPLINEMOVEParameter: Subdivision
MGTEXTOBJECT_SPLINESUBParameter: Shader Indexing
MGTEXTOBJECT_INDEXINGParameter: Effects
MGTEXTOBJECT_EFFECTORLIST_ALLParameter: Axis
MGTEXTOBJECT_AXIS_ALLParameter: Effects
MGTEXTOBJECT_EFFECTORLIST_LINEParameter: Axis
MGTEXTOBJECT_AXIS_LINEParameter: Align Height
MGTEXTOBJECT_AXIS_LINE_ALIGNParameter: Effects
MGTEXTOBJECT_EFFECTORLIST_WORDParameter: Axis
MGTEXTOBJECT_AXIS_WORDParameter: Align Height
MGTEXTOBJECT_AXIS_WORD_ALIGNParameter: Effects
MGTEXTOBJECT_EFFECTORLIST_CHARParameter: Axis
MGTEXTOBJECT_AXIS_CHARParameter: Align Height
MGTEXTOBJECT_AXIS_CHAR_ALIGN