I’m having the same issue, getting <2 MBPS on gigabit internet.
Neither the Engine.ini solution nor the Throttle limit are fixing the issue.
Also, the download manager numbers are all wrong. In the shot below, I’m getting only 1.76MBPS down, while the write activity shows a sustained 550MBPS.
This not only makes no sense, but also does not match Windows Task Manager, which shows a more appropriate 3.0 MPBS disk usage.
