When I put a custom tag into my Web Player Template, Unity won't remember what I set the tag to be.

1. I copied the example code found at the bottom of this page (http://unity3dhelp.com/Manual/Using%20Web%20Player%20templates.html) and put it in a file called index.html here: assets>WebPlayerTemplates>testTemplate.
2. I replaced the html title with the following: <title>Unity Web Player | %UNITY_CUSTOM_MYTAG%</title>
3. When I go to Player Settings>Settings for Web Player I am able to select "testTemplate". I can also see the variable "Mytag".
4. My problem is that, though I'm able to type something into "Mytag", as soon as I click anything else or push enter, my text disappears.

This requires me to manually change things in html rather than utilizing the custom tags. Have I done something wrong?