"Unless Renderosity is having a conflict with Comcast somewhere along the path" ... this would have nothing to do with Renderosity but how your ISP (in this case Comcast) routes and handles traffic to Renderosity. It could also be with the upstream providers along the way that feed into the data center we use.  Honestly this is the point I was trying to make before - that if it were strictly Renderosity's servers causing the issue - then you would get consistent results for everyone, every ISP, etc.  It's just not the case.  We have submitted a support ticket with our data center for them to investigate this issue since we haven't been able to replicate the problem on our end.  Also, we have a Comcast dedicated business line for alternate internet access in our offices - but we are not experiencing the slow download issues through that either. Ultimately it has to be a routing issue somewhere out there - we've noticed some high latency/lag times in some of the trace routes you guys have posted that we've asked our data center to investigate.  No word yet - we'll keep you posted.  Please let us know if anything changes on your end.  The more places you can test this from the better - to see if you are/are not getting consistent results through different ISPs.