Enabling multiple qty boxes and add to cart

I've got a feeling this should be easy, but I can't for the life of me figure it out, even though I've scoured the forums and done loads of searches, so forgive me if it is obvious...
I want to enable the multiple qty boxes and 'add selected items to cart' button on my product listing page.
In the Admin I've changed the 'Display products multple qty box status and set button...' to 3 in Product Listing, New Listing, Index Listing and All Listing.
Is it something to do with the way that I've configured individual products? They are virtual so the max quantity is set to 1, but I changed 'show quantity boxes to 0 instead of 1 to see if that made any difference, but it didn't.
Any help greatly appreciated!
Thanks, Cara.

These are the default settings of the Configuration ... Product Listing ...

Product Listing
Title Value Action
Display Product Image 1 Info
Display Product Manufacturer Name 0 Info
Display Product Model 0 Info
Display Product Name 2 Info
Display Product Price/Add to Cart 3
Display Product Quantity 0 Info
Display Product Weight 0 Info
Display Product Price/Add to Cart Column Width 125 Info
Display Category/Manufacturer Filter (0=off; 1=on) 1 Info
Prev/Next Split Page Navigation (1-top, 2-bottom, 3-both) 3 Info
Display Product Listing Default Sort Order Info
Display Product Add to Cart Button (0=off; 1=on) 1 Info
Display Multiple Products Qty Box Status and Set Button Location 3 Info
Display Product Description 150 Info
Product Listing Ascending Sort Order + Info
Product Listing Descending Sort Order -

NOTE: Products with Attributes will show the:

... more info

link as a choice must be made on attributes by the customer ...

Thanks very much for your reply Linda.

NOTE: Products with Attributes will show the:

... more info

link as a choice must be made on attributes by the customer ...
This is the critical bit I hadn't realised. I am assuming then, that as the products are downloads, and have to have a download attribute to work, that there is no way of enabling add to cart or multiple quantity boxes on the product listing page.

Since this question was asked back in 2006 I was wondering if there is anything that can be added to the discussion

I'm currently using version v1.3.9e

I'm in the same boat as Cara - most products are downloadable. Every product with an option attached is just the option to make it a downloadable product.

Is there any way to make these products able to add to cart from the category instead of having to click more info?