I'm trying to create links for a shopping trolley and can't figure out whether using the SS Forms/Button/Edit Form Item, needs special characters (e.g. <>") to be included, or if the edit function does away with the need for them.

I've been given the following coding which is 'guaranteed to work' but although I can make it work using it as a block of code (including the special characters) attached to one of my own made up buttons, I can't figure out what goes where when using an SS button.
<form action="http://www.fastcart.co.uk/cart/index.php" method="post" target="_top">
<input type="hidden" name="id" value="1223">
<input type="hidden" name="item" value="Big Blue Widget">
<input type="hidden" name="price" value="9.99">
<input type="submit" value="Add to Cart">
</form>

Try using a code object. The code you posted already looks like a complete form.