Remote HD

How do I manually un-install Remote HD plugin?

On the new AppleTV, SSH into the AppleTV and run this command:
dpkg -r remotehd-atv2; reboot;

On the old AppleTV, SSH into the AppleTV and run this command:
./uninstall-RemoteHelper

What is the difference between the full version of Remote HD and the lite version upgraded to a full version?

Under the hood, Remote HD Lite is the same product as the full version of Remote HD, with some key features disabled.
When you purchase the full upgrade from the iTunes store, Remote HD Lite enables these key features.

• The application name displayed in the iPad / iPhone / iPod Touch application list, will remain Remote HD Lite.
• The application remains linked to Remote HD Lite in the iTunes store. This has implications like you will only be allowed to rate or review Remote HD Lite instead of the full version.

After purchasing a full upgrade in Remote HD Lite, if I delete and reinstall the application, will I lose my upgrade forever?

No.
Full upgrade in Remote HD Lite is marked as permanent. Even if you do not back up your device after purchasing a full upgrade and reset your device, you can safely purchase Remote HD Lite and full upgrade again from the iTunes store without getting charged twice as long as you use the same iTunes account.

Is the full upgrade valid for only one device?

No.
Upgrades are not bound to a device. They are bound to your iTunes account. You can download Remote HD Lite and purchase the full upgrade on as many devices as you like. You will not be charged again as long as you use the same iTunes account.

When you purchase for the second time, iTunes will ask you to confirm a payment with full upgrade price again. Go ahead and confirm the payment. iTunes will then notify you that you already own a copy of the upgrade and will deliver the download for free.

Is Apple TV running software 2.4 supported?

No.
Remote HD plugin requires Apple TV 3.0 or newer.