Looks like OTG support is added to Files app today only. May be you might have to update the app and verify again.
The "Clear all recent tasks" isn't working quite right on 4.4. It seems the the location of the button is either too high onto the status bar or to low under the navigation bar. Here are some screenshots
If you are going to keep it on top you can...
Erm...what? Just flash OpenELEC on a SD and be done with it basically. H.264 videos play perfect out of the box for me even 1080p isn't any problem at all. The Pi is much better at playing videos (exception of DivX but who uses that anymore) than ...