In recent versions of the simulator Activity.Info.elapsedDistance always contains 0.0 whether I playback a FIT file or simulate data.
This happens with SDK 3.0.10, 3.0.11 and 3.1.0.beta2. It seems OK with 3.0.9 and earlier.
It's very easy to demonstrate with the SimpleDataField sample app that comes with the SDK.
I'm on Windows 7 x64 & Eclipse 2019-03 (4.11.0)
Simon