Hi @kool.sri,
It doesn’t look like you are doing anything wrong. Amazon appears to be erroring on a number of downloads and the speed does seem quite slow.
I did a quick download test from Amazon and the speed wasn’t great, but it wasn’t too bad (~7MB/s), so it may be that something is throttling your speed (Amazon or your ISP, for example), or Amazon is more impacted in your particular region.
If you want to send a diagnostic, I can take closer look at things. What you are doing is fairly straight-forward, aside from the very large scale, so there really isn’t much that can be done to improve Amazon’s performance. We do have some advanced settings that allow for tweaking download concurrency, which can potentially provide some speed-up by allowing more files to be downloaded at once, but these settings aren’t available in the free odrive version.