This issue has been resolved. Some Promo lines allow for seperate selections for each Group Buy when at different price levels. That explains why the "Available" count was incorrect.
There is a possible problem in using the Available Promotions options on the IK "Promotions" Page. It appears that if you access the Promo but back out of seleting a Promo, the "Available" button is not getting reset, so the Promo becomes unusable.
I recently did two Group Buys on the 25th Anniversary Promotion, each at a different price level. After registering the purchases, I went to the Promotions Page and saw the Group Buy promos, each line with an "Available" button.
I tapped an "Available" Button to get to the next page which shows the max price for selections available. After seeing which price category the Promotion offered, and without making any selection, and thereby obviously not "Confirming" a selection on the following Confirmation page, I backed out to the Promotions page, and quickly noticed that the "Available" button on that line did not reset, but showed "Downloaded". I had done this once before on my first Group Buy, but didn't notice that the Available button did not get reset because of all the other Promo lines. However, when I did the same process yesterday, I counted the number of Available buttons before tapping one. Then when I backed out, it was not getting reset!
I just filed a Support request to IK-US Sales/Promotions team explaining the possible problem in detail, and asking if they can provide a reconciliataion between the Promos made available and which products were selected (or downloaded/registered) I did a reconcile against the "My Products" page and correcting for the Original products ordered on the two Group Buys, and I did indeed find that I appear to be two products short (having backed out on two different Promo lines. Unfortunately, when one submits a Support Request, there is no immediate confirmation that it was received, so I am posting this notice to the Community.
If anyone knows ( @Peter-IK Multimedia ) of a better way to reconcile Promos to actual products ordered, please post, otherwise need to wait for a response from Support.