Project Monitor does not support deploying to a sub-URI

[SQUIDwarrior]

I am attempting to deploy Project Monitor on a sub-URI "http://my.company/monitor" using Passenger and Apache. I have followed the instructions on the Passenger web-site, and I can get to the main page from my sub-URI, as well as the "manage projects" link to edit. However the main page is blank. Looking at the page source, all the assets are being prefixed with "/monitor", but when I look at the Apache log I see errors trying to query "/projects":

[Thu Aug 20 10:01:44 2015] [error] [client X.X.X.X] File does not exist: /var/www/github_status.json, referer: http://Y.Y.Y.Y/monitor/
[Thu Aug 20 10:01:44 2015] [error] [client X.X.X.X] File does not exist: /var/www/heroku_status.json, referer: http://Y.Y.Y.Y/monitor/
[Thu Aug 20 10:01:44 2015] [error] [client X.X.X.X] File does not exist: /var/www/rubygems_status.json, referer: http://Y.Y.Y.Y/monitor/
[Thu Aug 20 10:01:44 2015] [error] [client X.X.X.X] File does not exist: /var/www/projects, referer: http://Y.Y.Y.Y/monitor/
[Thu Aug 20 10:02:14 2015] [error] [client X.X.X.X] File does not exist: /var/www/version, referer: http://Y.Y.Y.Y/monitor/