Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See Parameter IDs.
Parameter: Time
TIM_TIMEParameter: Extend
TIM_EXTENDParameter: Single
TIM_SINGLEParameter: Animation Time
IN_TIM_ATIMEParameter: Start
IN_TIM_STARTParameter: On
OUT_TIM_ONParameter: Time
OUT_TIM_TIMEParameter: Time In Percent
OUT_TIM_PERCENT