ok in order to increase the speed do this.....
right click on the file in the downloa queue.... and the go to bandwith and select maximum bandwidth speed.... next ..right click on the file again go to upload speed and set it 1kbps..... if it doesnt show 1kbps on the menu...start with 10....right click again go change it to 5 and then again to 3 and so on......
and also on the settings...under network select randomize port....
if u want to get a quick speed boost right click on the file click update tracker...
that's all i know....i usually do above steps to increase the download speeds.