I (re)tested COPS 6.1 (Github) on my Synology DS110j.
[DSM 4.3-3776 : 2013/08/17]
I did not test everything, just the basic functionality
Findings:
- OPDS clients => worx
- Firefox (OSX & Windows) => worx
- Internet Explorer 10 on Windows 7 => worx
- Safari on iOS 6 (iPad 3 and iPhone 4) => worx
- Safari on OSX 10.8.4 => worx
- Safari on OSX 10.6.8 => problems with showing covers in lightbox (see added screenshot) User agent info in second screenshot. [longshot: it can have something to do with caching, I will clean the cache when I'm finished with some other browsing tasks]
{do not try to fix this, as Safari has no ePub-reader plugin, so is pretty useless for reading e-books 
}
- when opening COPS in a browser it sometimes takes some time before the grey window shows something. the server is not busy (tested with top) and the client is fast enough (Intel Core 2 duo 2.0 GHz). This also happens (most noticeably) when I go to the menu item "recent additions". the screen does not change for some time giving the impression nothing happens (but the browser is hard at work, CPU goes up but not to 100%.