Seems like on avatars uploaded after the newest update that use aim constraints flip the aim constraint up vector on the Y axis 180 degrees.
This basically breaks aim constraints that need a specific up direction.
This issue is NOT present in unity, and only happens ingame after uploading the avatar.
In these images are 3 aim constraints (with very slight setting variations) all pointing towards the floor at a point, the L faces upwards in unity. Ingame they all flip downwards instead.