Install the latest WINE stable build from your local package manager. In my case, (elementaryOS/Ubuntu/Debian variant) that would be: sudo apt install wine-stable
Install Winetricks: sudo apt install winetricks
Open Winetricks and follow the prompts below.
It may show you an error saying these warnings:
dotnet40 does not yet fully work or install on wine. Caveat emptor.
Mono does not appear to be installed.
Running /usr/bin/wineserver -w. This will hang until all wine processes in prefix=/home/sprite-1/.wine terminate
But that's fine. Just click OK and continue through these.
The setup for .NET 4.0 should start to load up.
Just install it normally and after the installation is completely done, open up the MEGA Link Downloader installer with WINE.
Proceed with installation as normal. You don't need to check the "Create a desktop shortcut" option in the setup.
A text file should open up after installation. Just close it.
Lastly, go to ~/.local/share/applications/wine/Programs/MEGA Link Downloader/
and delete "Uninstall MEGA Link Downloader.desktop" so the uninstaller doesn't show up in your app list.
You're done!