PayPal extension not working on webpage

I am very new to Dreamweaver, PayPal and web design/development in general. Am trying to add PayPal to a webpage, but it does not function. I have a PayPal account and worked through the wizard. Here is my code:

<p><strong>Please select only one item!</strong></p>
<form action="https://www.paypal.com/cgi-bin/webscr" method="post" target="paypal" id="paypal_order">
<p>
<label>
<input type="radio" name="RadioGroup1" value="radio" id="RadioGroup1_0" />
Website 50% Deposit</label>
<br />
<label>
<input type="radio" name="RadioGroup1" value="radio" id="RadioGroup1_1" />
Website Balance Due</label>
<br />
<label>
<input type="radio" name="RadioGroup1" value="radio" id="RadioGroup1_1" />
Website Payment in Full (optional)</label>
</p>
<p>
<input type="hidden" name="cmd" value="_xclick" />
<input type="hidden" name="bn" value="webassist.dreamweaver.4_5_0" />
<input type="hidden" name="business" value="linda@pathtoweb.com" />
<input type="hidden" name="currency_code" value="USD" />
<input type="hidden" name="undefined_quantity" value="0" />
<input type="hidden" name="receiver_email" value="linda@pathtoweb.com" />
<input type="hidden" name="mrb" value="R-3WH47588B4505740X" />
<input type="hidden" name="pal" value="ANNSXSLJLYR2A" />
<input type="hidden" name="no_shipping" value="0" />
<input type="hidden" name="no_note" value="0" />
<input type="image" name="submit" src="http://images.paypal.com/images/x-click-but02.gif" alt="Make payments with PayPal, it's fast, free, and secure!" />
</p>
</form>

Thanks for help and PATIENCE!

It looks like you are missing two parameters:

<input type="hidden" name="item_name" value="Itemname" />
<input type="hidden" name="amount" value="2" />

the item name and the item price. once you add those to your form, the button should work correctly. Those fields should have been created when you clicked OK. One thing you can try is reentering the wizard by clicking on the paypal button in design view in DW and then open the Properties window (Window -> Properties) and click the edit button and make sure to specify a total and a name for the product.

Thanks, Dani! I added these parameters, got it to work for the most part, other than some tweaking, but I am a little confused. The wizard indicates that these parameters are optional. My website offers services as opposed to tangible items and the costs vary, so I do not want to hardcode an actual amount. How do I get around this?

You could get the value from a recordset, session variable, or other source. I think the name is always required. The amount is required for a cart item, but can be blank for a donations button. The only way to get around all of the limitations is to use something like the WebAssist eCart.