e-commerce store limit?

We created an e-commerce store, created 55 items, and added them to the store.

So, in the E-commerce - Stores, step 3. Select Products, all 55 products show in the right column (Your Selections). Yet when we save and preview the store, it only shows about 40 products. Where are the other 15? Is there some kind of built in limit to how many products you can have that is not mentioned or documented in the help files?

Any help would be appreciated.