there's no magical way to make something upload faster
i'm p sure uploading saves in-game is bottlenecked by packet rates or something goofy like that. there was a topic about it ages ago, idk if it was disprovbved or not
if that's the case, though, actually downloading the file on the server-side would be faster. you can easily do this through torquescript, but blockland doesn't support HTTPS, so some sites wouldn't be an option (namely dropbox since they now force HTTPS what a bunch of jerkholes)
on my VPS i had to rig up a system to download files from a local python server to get around this, but it might not matter for you, esp if you can just use FTP or something
If you can't find any way of doing it, if I'm not mistaken, setting the timescale to 2 increases the speed. Don't ask me why, but I'm pretty sure it does.
if this is the case, there likely is some kind of artificial limit on packet transfer