Hi,
I’ve just checked and the lastest version of Download Manager (v4.8.1.1) has been installed but the problem still still persists,
“Something went wrong. Your change may not have been saved. Please try again. There is also a chance that you may need to manually fix and upload the file over http://FTP.”
I can see in the changelog is talks about v2.9.85 having “Fixed the conflict with the wordpress plugin/theme editor”.
Please update as soon as possible.