V38.0.1 setMapCollisions issues

Looking into the changes for v38, I am running into issues with the websocket setMapCollisions.

Edit: Resolved at least part of the REST API thing.

For the Websocket, setMapCollisions sends back
[error from gs] 400: update index is out of bounds of collisions
I am converting the new collision data format to the correct byte array string, and I have compared it against the same data from the RestAPI to confirm. For my use, I am attempting to repaint all of the collision blocks in a room, so get/setImpassible really does not do what I need.