I've been experiencing them with up to RC4, I just installed RC5 a few minutes ago, but I assume that this issue was not fixed in RC5.
Multiple internal crashes occur and then the download speed drops to 0 and stays 0 untill Newsbin is restarted.
This issue seems to be occurring with incomplete posts, such as with posts of HBO shows with first segments deliberately removed from each file.
Or with very incomplete posts.
I think it could be quite easy to reproduce the issue by trying to download such incomplete files. Especially if many and of significant size.
You only need to be a bit patient, it may occur after 30 minutes or after a few hours of downloading.
BTW, I am still on 32 bit windows XP. Sorry for that. Maybe it is only on this archaic system.
Still trying to choose the mobo for my new computer with 32 or 64 GB of memory. 4 months and counting ....