Aborting those uploads will mean that after 4 resends they hit there max resend number and be removed from the server.

You have only 3.89 GB of memory. That isn't enough to run even one work unit here (except the small ones).
You should start out with 6 GB for the first one, and then add at least 4 GB more for each additional one.

Also, the anti-virus might be interfering with the process.

2 - You're nowhere close to 90%. 754/1286 is 58%. Still pretty bad.