Hellow,
I followed this tutorial http://mrtrix.readthedocs.io/en/latest/tutorials/hcp_connectome.html, and I have some problem to download the data, as i use chrome on my MAC, so I followed the advice to enable the plugin after I installed Aspera connect on my mac:
NOTICE: If you are using Chrome and are having issues with the Aspera download plugin, please navigate to chrome://flags/#enable-npapi and enable use of NPAPI plugins. An anticipated Aspera update should resolve this situation.
But in the page chrome://flags/#enable-npapi, i did not find the option to enable the NPAPI plugins,
So i always got the error like this: 
I dont know why, but it seems that aspera have some bug for chrome, so I change to use safari, still the same error…
Any advice will be appreciated
Thanks in advance