I'll try to help as much as possible, but first..
How to Install APK Files on your Nexus Player
[If anything breaks, I take no responsibility. You just voided your warranty, do this at your own risk. Yadayadayada.]
I was stuck on trying to install APK files, as I had updated my Nexus Player to Android 5.1. The 'ES File Explorer' method did no longer work, so I struggled and struggled on how to install APKS, specifically, a web browser.
1. Download the SDK Platform tools. (http://forum.xda-developers.com/show...8#post48915118 is a simplified version)
2. Download official Google ADB drivers, assuming you are using Windows. (should be here: http://developer.android.com/sdk/win-usb.html)
3. Go to Settings on your NP. Go to 'About Devices', then click on 'Build Number' repeatedly. Go home, then go back to Settings. Look for Developer Settings, then enable USB Debugging.
4. Connect your Nexus player into your computer using the MicroUSB port.
5. This is where it all depends. If your computer recognized it, perfect, skip to step 7. If it didn't, then don't worry, I got you.
6. Click on the Start button. Right-click on Computer, and select Manage. Click on 'Device Manager' on the left pane. You should see "Android" with an exclamation mark. Right-click on it, and select "Update Driver Information" (or something in the midst). Click on 'Browse', then select the folder you downloaded. (You should unzip the drivers, if they're zipped). It should say something like 'Samsung Composite Google Device' or something like that. Just click okay and continue.
7. A popup window should appear on your tv, click 'Always Trust' and 'Ok'.
8. FINALLY! Download your APK file. [use responsibly guys]
9. Put the APK file into the platform-tools folder.
10. Shift-right click on the window (you should be on platform-tools for it to work), and click 'Open Command Prompt Here'.
11. Type in 'adb devices' without the apostrophes.
12. Your device SHOULD show up, as a string of letters, or simply Nexus Player.
13. Now type in 'adb install APKNAME.apk' without the apostrophes, and APKNAME.apk being your APK file.
14. Follow steps on your TV.
This method does needs Chainfire's Sideload Launcher, as far as I have tested. I'm going to install: Google Chrome, Spotify, and reddit is fun. I'll report soon to see if those worked.
By the way, if the whole driver thing doesn't work, just google 'ASUS Nexus Player Google ADB Drivers', they should show up. I don't use OS X, and barely know Ubuntu so I can't help out with those. I'll be trying to help as much as possible; I'm still a student lol.
As for showing gratitude, just a simple click on the Thanks button and/or getting the post popular makes me feel like Woz.
EDIT: Spotify is rotated counterclockwise 90 degrees. [FIXED: GET THIS AMAZING APP: https://play.google.com/store/apps/d...ntation&hl=en]
EDIT: Chrome Beta is not working whatsoever. Same with regular Chrome.
EDIT: Firefox works perfectly.
EDIT: Found an application, converts all applications that are flipped and what not to landscape mode. (https://play.google.com/store/apps/d...entation&hl=en)
EDIT: reddit is fun semiworked, only scrolling
Just install Air Share from the Play Store if this is too hard for you.