ROS2 to ROS1 Conversion Error

Many thanks for the project. I have been testing using the following bag for the ros1 to ros2 and back conversion.

http://robotics.ethz.ch/~asl-datasets/ijrr_euroc_mav_dataset/vicon_room1/V1_01_easy/V1_01_easy.bag

Example:

pip3 install rosbags==0.9.11
rosbags-convert V1_01_easy.bag --dst bag1to2/
rosbags-convert bag1to2 --dst bag2to1.bag

I get the following error:

ERROR: Converting rosbag: TypesysError("Type 'asctec_hl_comm/msg/MotorSpeed' is unknown.")

I understand from the wiki that only the standard ROS2 types are supported, but currently the conversion will just create an invalid bag instead of converting the ones that are supported (e.g. the camera, IMU, and transform topics in the bag). Is it possible to add this? I am not sure a easy way for people to filter existing ROS2 bags, thus it would be nice to convert the known topics successfully instead of just not converting anything.

I also tried removing the topic /fcu/motor_speed from the metadata yaml file metadata.yaml but this also errors for me with

ERROR: Converting rosbag: AttributeError("'NoneType' object has no attribute 'msgtype'")