[kamocat]

The "get position" reporting zero is one of the bugs in the current Jaguar firmware.
"get position" reports zero until the position reference has been set and Position Mode has been enabled. After that, you can read position in any mode.
Likewise, "get speed" reports zero until the speed reference has been set and Speed Mode has been enabled.

Additionally, "get speed" always reports positive, regardless of the direction the encoder is turning. However, speed mode works just fine in a negative direction.