Finger rotations not importing correctly for humanoid project

Hi, I've been using UMotion Pro a lot and love the asset, but this is the first time I've had issues with fingers not animating properly.

I'm using a Humanoid project because my end goal is to convert generic animations I've created and convert them to humanoid animations. My usual workflow is:

1. Import FBX of model + animation into Unity

2. Change Rig structure of model from Generic --> Humanoid

3. Create a new UMotion Humanoid project

4. Set the humanoid model in the pose editor

5. Import the generic clip from the FBX

6. Export the clip (which now saves as a humanoid clip)

However this time, the fingers aren't animating at all when I import the clip (step 5) in my humanoid project: 

The fingers animate fine if I test against a generic UMotion project (not converting to humanoid) though:

I inspected the humanoid avatar, and it looks like the fingers are bending correctly for a humanoid rig:

Can you help me fix the fingers not curling in my UMotion humanoid project please?

Much appreciated

Dat