This is why internet download manager (and other, similar download manager softwares) were originally created. Download managers track the amount of a file you've downloaded and will repeatedly retry when interrupted without restarting from zero.
Getting Warez in the pre-P2P era meant grabbing bits and pieces over a glacial ISDN or 33.6k modem line (if you were lucky- some of us bastards got 28.8k, or even 14.4k...) Everything was "direct download". You had to use a download manager for anything larger than 30 megabytes because the chances of your line being interrupted were very very high, either by other phone users or by your ISP booting you off because you looked like a zombie modem being connected for 24 hours straight.
They still have their place. Try something open source like JDownloader. Or just pirate the pro version of IDM.