Maybe your internet is unstable, its enough that its gone for less than a second ("reconnects") that some filehosters instantly drop the connection of the download.
Then in your browser it displays Network error for the regarding downloads. I experienced this in the past when my internet was unstable.
When I saw that Network error in my browser the first time I went and checked also my torrent software and saw that internet speed collapsed completely.
It went down to 5kb/s in download and upload, then it reconnected with all the seeders and peers again and went up to max speed again after a few seconds.
On some days it happened a lot, on other days not at all or only a few times. Gladly after a month the internet went back to normal by itself.
You could check with tools if you have high Packet Loss or monitor your internet connection the whole time when you´re using it to see how stable it is.
Besides that you could also try a different browser or a download manager like for example JDownloader; just to make sure the browser isnt the cause.
Of course its also possible that the cause is on rapidgator´s side, was never a fan of rapidgator myself.
You might as well just ignore it, the world is not gonna end because you need a little bit longer to download something.
I leave all my downloads running in the background while enjoying myself with watching movies, playing games, listening to music or something else and if a download crashes I just download it again later.
I understand that you wanna use that premium account to the fullest, but lets be real:
how much of what you download there will you keep for the longrun (10 years later) or rewatch?
Its actually better to use ur time to have fun than trying to look for solutions which might take hours upon hours of your precious time and in worst case nothing changed besides that you wasted time.
Why spend time like that when you can have fun in the same time. Life is to short ^^
Shine