Update 2016-03-12
This issue should now be fixed. If you're still experiencing issues, it would be very helpful if you could upload the replay to another site (e.g. http://wotreplays.com/) and send me a link (click for contact info).
Once again, apologies for any trouble this caused and thank you for your patience.
Original Post
I'm aware of the issue where attempting to upload certain 9.14 replays causes an Internal Server Error. My apologies for the trouble.
It is not an issue I can reproduce with Random battle replays, which are the only ones I have currently. If you're unable to upload a replay to the site, it would be very helpful if you could upload the replay to another site (e.g. http://wotreplays.com/) and send me a link (click for contact info).
Thank you for your patience.