Possible bug with options after upgrade

We are using options to present sizes, colors and material options as suggested in an earlier post:
www.hikashop.com/en/forum/4-how-to/77999...ptions-possible.html

Making progress though the option descriptions did not display in the cart so the customer had no opportunity to review what they'd ordered. So I looked at the demo site trying to figure out if there was some configuration option we'd missed, noticed the newer version running so upgraded our site.

Perhaps coincidence, but began seeing a number issues after the upgrade:
On the front-end, multiple messages are displayed "Product is not available"...each product being a product option.
Options presentation has changed on the front-end. Some options now present a single item in a combo box where there should be multiple.
The order of items in the combo box has changed in another product option.

Any ideas as to what may be causing the behavior described?

Hi,

You have updated to the 2.1.0 ?
The update should not edit the options and the display of the options.
Are you sure that you don't have changed an option recently, or edited the products (stock, variants..) ?

Yes, the upgrade was to v2.1 last night 2/11/2012.
At the time of the upgrade, I had items in the cart in a front-end session. I had not made changes to any products, was only looking around in the back-end trying to figure out how to include option descriptions in the cart when I noticed an upgrade was available - so installed the upgrade.

After the upgrade, I returned to the front-end / checkout and got several messages:
The product Vinyl Color is not available
The product Mirrored Image is not available
The product Material Type is not available

When subsequently viewing parts using these options, some of the characteristics of the product options are no longer presented - I confirmed they still exist and appear valid otherwise. And one option (size) that does present all the characteristics has change the order of presentation in the combo box.

On the chance that something had happened to the options and characteristics created, I created a new characteristic with 2 values, a new product using the newly-created characteristic and added the new product as an option to an existing product.

I'm seeing the same behavior, only one of the characteristics is being displayed. Adding the item to the cart yields "The Product (product name) is not available".

All our products are "unlimited".
The option "Display 'add to cart' button for free products" is set to "Yes".
We do not have prices set for all product options as some present information on how to fill the order, but doesn't affect the price.

An option created to select a size was sorted numerically by size. Now they're presented in the order:
4"
20"
5"
6"
7"

One of the options we created is essentially a "Yes/No", only the "No" option is presented on the front-end
Another option was setup to present choices "Permanent / Removable", only the "Removable" option is presented on the front-end.

I've verified the SQL is returning all the characteristics and in the correct order, they're just not all presented, and not in the correct order (e.g. characteristic_ordering).