Fugue with a subject from an internet stranger

One day a couple of weeks ago, I found this post on /r/composer where some guy (/u/AHG1) wrote a fugue for organ when he was a teenager. Anyway, I thought the subject was interesting, so I decided to do the fugue my own way. The original composer supported my endeavors as well, so I'm happy that he can finally see what I've come up with.

This isn't a particularly unique fugue in my opinion, but any and all comments are of course welcome regardless.

https://drive.google.com/drive/u/0/folders/191AToucbt0E9Py-6MqM0y_22IHwqxq6R

This job sounds great. 
I have not reviewed it in depth, but it seems to me that it does not follow standard fugue tonalities in terms of subject and response. Either way, I think it is very well constructed.