Can I export the assets to Blender/Unity?

[Raborick]

ENT and MAT is only usable in HPL2.
You can open DAE in Blender. Just click File > Import > DAE in Blender.

As for importing to Unity, you could import the DAE and re-export it as another file that is supported by Unity.
QUICK EDIT:
The Textures are DDS, you can open them in GIMP (plugin required).

tyvm i didnt know dae opened in blender.