Tvheadend

Hi, new tvheadend user here, so please be gentle. I was able to login, but then:

I'm getting this common web server error, which is a permission issue it seems. I did a search prior to posting and found a bug (5573) from 8 months ago, which appears to be fixed (attached). Is this the same bug affecting me? I installed from the 'mamarley-ubuntu-tvheadend-git-eoan' repo, so I assumed that this would probably be setup correctly — I'm using Ubuntu Eoan.
What do I change to get this fixed?
Thanks!