UE 4.26 Megascan plugin content broken

Hi,

The bridge export in UE 4.26.0 works fine (textures are getting exported, and a copy of master material is being made in Content folder), but some of the actual master materials in the plugin content are broken.

STEPS TO REPRODUCE:

1. Install Unreal Engine (4.26.0) and bridge (2020.4.2)

2. Install plugin using Bridge via "Export Settings"

3. Create new project

4. Enable "Show Engine Content" and "Show Plugin Content"

5. (Optional) Filter the assets using "Material" type

6. Open any of the following materials (these are the ones using one or more Material Functions): GlassMasterMaterial, MS_DefaultMaterial, MS_DefaultMaterial_Displacement, MS_DefaultMaterial_Fuzzy, SurfaceBlend_MasterMaterial

and so on..

ADDITIONAL INFORMATION:

1. On clicking on one of the "Unspecified function" nodes:

2. If I manually fix by assigning all functions in the graph (test case: Glass Material), then it shows an error within one of the material function:

3. On opening that material function, it shows:

4. There are no "Imperfection Map" named texture in the folder. The only texture i found was a roughness sample texture (4K), which I assigned to the parameter as default:

After all this, the Glass material started to work, but this process has to be repeated for all materials which are not working. Furthermore, I reinstalled the plugin by deleting the existing Megascan plugin folder and repeating step-2 (see above), and all the references I had setup were gone; meaning if there is an update for either plugin or UE4 itself, I'd have to do this all over again.

I hope it gets fixed soon. If there is a way I can contribute, then please let me know. I'd be more than happy to send the fixed uasset files for all the base master materials.

Thanks,

Punya Aachman

P.S. Sorry for the long post.