I have set up an OpenRailwayMap tile server on Ubuntu via this page:https://github.com/rurseekatze/OpenRailwayMap/blob/master/INSTALL.md

I am no trying to test it via requesting a tile with a URL like:

This just returns a blank page, with no features drawn.

I can see the request come into node-tileserver
[2016-10-13 17:21:41.054] [INFO] [default] - Request for /standard/2/3/1.png received.

I can also see the folders and *.json files being created here:
/home/www/sites/194.245.35.149/site/orm/tiles

However, the *.json files only look like this:

{"features":[],"granularity":10}

I have successfully imported the data into PostgeSQL, and can see the data in all the tables.

Any idea what I am missing?

-- Matt