Sorry tech didn't keep the links but Free Download Manager downloaded the URL to the download site instead of the actual file if that's of any help.
You need to add html and other webpages extensions to not be downloaded by FDM.
Indeed, for me, if you add a link to 'another donwload page', the ones having a phrase like this: 'if your download does not start immediatly, click here' or something like that, FDM process the link and goes further until it finds the real link to download the file...
As I can see, something is different in your system (with FDM maybe...).