I can't login with Salesforce credentials when using dataloader.io

I have been working on the following challenge: Use Dataloader.io to Export Data

From Setup, enter Dataloader.io in the Quick Find box, then select Dataloader.io.

Click Launch dataloader.io.

Click the Confirm button. 

Click Login with Salesforce. - At this point when I try to login to dataloader.io I get an error "404 not found"

Is there any work-around to finish this challenge?

Thanks