Downloading issues

I’ve done everything until i could start the download. I don’t have a great connection so for me it’s a real problem to download 66go because i can download around 1go/hour.
Even if it was painfully long i still went with it letting my pc download over night. But when there was around 28 go left it started to slow down. One night downloaded me 2 go… (the same speed was shown around 330ko/s)
When 25 go was left to download it started to get better so i went with it so i close the app and my pc for the night. But then when i wanted to restart, it went back to 66go… (it wasn’t the first time i would stop and resume the download) I still have the content that i had downloaded (the ARKDevKit folder is 48.8go) and in the launcher i don’t see any sign that it’s not downloading in the right folder.

On this point i don’t know where to head to resolve my problem.