This story was really really good, I can see the hours of effort that have gone into it and it really shines. My main criticism was that the lighting was awfully dark and no ambient lights were used most of/all of the time. I'm not sure if that is what you were doing on purpose, but if you put in some very dark ambient lights, it would greatly improve the story.
I loved so many things in this story, my favourite bit was when
It did feel like a custom story, and didn't have a very proffesional feel to it, although it is very well polished and I had no experiences with overlapping textures.
Ultimately, I thought it was really fun and the voice acting/flashbacks was nice to see/hear in a custom story.
I look forward to playing any new content that you create!!