Is it possible to have multi-thread cURL with Flashgot in Ubuntu?
Solution 1:
The latest version of uGet has cURL multi-connections built in without the need of a plugin.
http://uGetdm.com/
I know you are already aware of uGet as you stated in your question but not sure if you're aware of the latest version new cURL features.
Solution 2:
To get a multi-threaded downloader which integrates with FlashGot, you can install uget and aria2
sudo apt-get install uget aria2
Then, go to uGet's settings and enable the aria2 plugin.
uGet will also show up on FlashGot's list, where it can be selected for browser integration.