Changing from Selectboxes to Checkboxes

[Agiliteesgal]

After too many years, I have thrown in the towel on Zen Cart and have decided to give AbanteCart a try. So far, I'm finding it so much easier to navagate, but I have run into a little problem that I hope someone can assist me with. I am a tee shirt printer and need to set up my store so people can order shirts in various sizes and colors. At first, I set things up in the Global Attributes to use multiselectboxes. However, as I input products and played with various options, I decided to change to checkboxgroups instead. I switched to checkboxgroups in the "Attribute Type" dropdown field in the Global Attributies section (and saved my changes), but the product pages still displayed the multiselect boxes. Today, I added two new color choices in the Global Attributes. To my surprise, the shirts with the "new" colors display checkboxes on their product pages. However, my earlier products are still displaying multiselect boxes.  (My husband, who is a long-time software engineer, thanks that perhaps the php files are not being re-rendered when changes are made to the Global Attributes.) Can anyone help me with this?
Huge Thanks!

[abantecart]

It is important to remember that Global Attributes act as template setting that can be applied to products.
Changing Global Attribute type will not automatically change all products that use this attribute.

It is tricky if we allow updates of all products that use given Global Attribute that is changing.
This is something that we consider to improve in the future