Pause and resume downloads (even broken ones), keep your downloads organized and increase your download speed.
— Does it require key or is it fully activated?
This is a shareware application meaning that you'll have the possibility to test it for 30 days and afterwards it needs to be purchased to enable its functionality again. After 30... days the software will actually cease to work, and every time you'll want to start a download, a registration window will pop-up.
Download a trial version through the download page at Software Informer: http://internet-download-manager.software.informer.com/download/
You can buy it on the following page: