Make sure your diffuse texture (that's the texture with the models colors on it
) is applied in the models material in your 3D program before you export. Also make sure the texture and the .mat file are in the folder they're supposed to be! (Look at the folder structure of the original Amnesia models for reference.)
The reason for this is that Collada seems to get confused if it doesn't find an applied texture on the model and produces a broken .dae file that can crash the model view (and the model editor too, I suppose). Or at least, that was the problem I had, there are probably a ton of other things that can make hpl tools crash...