Popestt: The ART renderer attributes, although operational, have not been fully integrated into the interface yet. Anim8or V0.97c & V0.97d have the renderer built in, but they are only preview releases, designed to allow us to test the new features. As such, the current method of accessing these features is a little awkward, but not so complicated really.
Basically, by adding attributes, what you are doing is inserting new variables into the code of your project, variables that affect the way the ART renderer operates. Variables must first be defined, and then assigned a value. For example, one of the ART attributes is a reflection raytracer, perfect for your model above. It derives its value from the Specular setting in the material editor, so a specular setting of 0 yields no reflection, and a setting of 1 yields a mirror finish. Before the ART renderer can use this variable, it must be defined.
In the Material Editor for the material you have applied to the tap, click the Attributes button. The window that appears is a simple interface designed to allow to you add variables into your project. Any variable can be added, but only those variables recognised by the ART renderer will have any effect. If you click New, you start to define a new variable. The names of the recognised variables are included in the documentation (see floyd86's post above for the link) and must be entered exactly as supplied, case sensitive.
In the blank text field that pops up when you click New, type the word "specular" (without the quotation marks) then click Ok. Next, you must define what sort of variable it is by clicking the correct variable type. In this case, click String. In the text box at the bottom of this window that has just turned white, type the word "reflection" (again without the quotation marks). Finally, click Ok to return to the material editor window.
The value of a variable can vary in type, for example, one variable might have a numeric value, another might have a text value. So the effect of this operation was to add a new variable to the project, called "specular", it has been defined as representing a text value (string), and has been assigned the value "reflection". Now, when the ART renderer is running, it will know to calculate ray traced reflections for this surface, and it will use the Specular value to define how reflective the surface appears.
All the ART attributes are defined in this way. Check out the link mentioned above and have a play with each of the attributes, the best way to get to grips with something is to experiment with it. Oh, don't forget to change the renderer from Scanline to ART in scene mode.