Bendy ruler,with rp lidar

Hello,
i have a question about bendy ruler.I managed to connect an rp lidar to pixhawk and get some measures,then i tried to enable the object avoidance feature,so i did the configuration below:
AVOID_ENABLE = 2 (“Use proximity sensor”)
OA_TYPE=1 (“Bendy Ruler” )
OA_LOOKAHEAD= 5m
OA_MARGIN_MAX= 3m
the first problem i encounter is that the options about the obstacle data base are not available (i refreshed the parameters and reboot ardupilot).The second problem is that when i experiment with the feature (in Auto mode)the rover just stops in front of an obstacle rather than try to dodge it,and continues its mission when i remove the obstacle.(firmware Rover 4.0.0)
Any advice would help…
Thank you