Hello,
I've made some small isolated tests to understand the limits and I had some issues with strokes and masks. I'm almost sure the problem comes from "Create shapes from vector layer", but I'm not sure why or how to fix it.
I'm using version 1.5.3.
And this is my workflow:
Here's a ZIP containing: .aep, .ai, .html, .json and .mp4: lottie.zip
Here's the expected:

Bodymovin's version:

Lottie's version:

Well here's what they look like in 2.0.0-beta2 :)

Enjoy!
And what they look like with merge paths enabled (KitKat and above only):

Marvelous! (:
Most helpful comment
Well here's what they look like in 2.0.0-beta2 :)

Enjoy!
And what they look like with merge paths enabled (KitKat and above only):
