Welcome @Nik
Thank you for reporting the issue! The environment most tools run inside of was updated over the last several weeks, and it seems this tool was impacted!
I am generating a test case and will open a ticket to let the server administrators know what is going on. I’ll post back the details in a few minutes.
Meanwhile (and completely optional), if you would also like to send in a bug report from one of these errors, that will likely be helpful. Click into the 
icon form one of the red datasets. You can include a link to this topic in the comments for context, then submit.
More soon! 
Reported now! The server is undergoing other changes today so this may be addressed by those but if not, they’ll see the outstanding problem and correct it, then let us know! 
Thanks again and apologies for the confusion. The legacy tool is not hosted at the other UseGalaxy servers so I don’t have a good workaround – we’ll need to wait.