Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See Parameter IDs.
Parameter: Default Format
PBODYPAINT_DEFAULTTEXTUREFORMATParameter: Show on Mouse Move
PBODYPAINT_SHOWBRUSHMOUSEMOVEParameter: Show while Painting
PBODYPAINT_SHOWBRUSHPAINTINGParameter: Tool Cursors
PBODYPAINT_TOOLCURSORParameter: Pixel Border around UV Poly
PBODYPAINT_PIXELBORDERParameter: Tile U
PBODYPAINT_TILEUParameter: Tile V
PBODYPAINT_TILEVParameter: Project on Invisible Parts
PBODYPAINT_PROJECTONParameter: Ignore Unpaintable Geometry
PBODYPAINT_PP_PROJECT_THROUGH_UNPAINTABLEParameter: Border on Same Object
PBODYPAINT_BORDERONParameter: Continue UVs on Border
PBODYPAINT_CONTINUEParameter: Preview Width
PBODYPAINT_FILTER_WIDTHParameter: Preview Height
PBODYPAINT_FILTER_HEIGHTParameter: Show Source Preview
PBODYPAINT_FILTER_SHOWPREV