Buy x get y coupon not working for most customers

Hey -- so I have a buy 2 get 1 free coupon set up. I am using Joomla 1.5.17 and VM 1.1.9. It's for a lash site 3d-beauty.com

I have been getting a lot of complaints that the code isn't working, and I can see that it has only been used once, so that is likely true. Though it works fine every time I log on and try to use it. I also seem to be missing the checkbox "Automatically add to cart 'Get Y' product" -- I didn't even know that was an option till reading these forums to try and fix this!

Am I screwing up the settings? Here are my settings:

Function type : coupon
Function type 2 : Buy X get Y
Coupon Code : LASHX419
Published : Published
Percent or Amount : Percent
Value : 100.00000
Process Type : First Found Match

Numbers of Uses : 10
Minimum Value : BLANK
Maximum Discount Qty: BLANK
Start Date : 1 April
Expiration : 15 April
Don't Mix Products : checked
Admin Note : BLANK

Customers : BLANK

Buy X:
Number : 2
Type : Category (three categories selected)
Include Selected

Get Y:
Number: 1
Type : Category (three categories selected)
Include Selected

Thank your help!

Hello,

You will need to have the latest version of AwoCoupon installed to see the checkbox.

For the number of uses, is that per customer? If so, then the customer is required to log in before using the coupon code. Maybe this is where the problem is, customers are trying to use it not logged in. You can go to awocoupon->configuration->error messages and change the not logged in error message to something more user friendly so the customer understands they have to log in to use it.