After using 1.x, wanted to test 2.x to test the products import.

Got PHP Fatal error: Unsupported operand types in /home/web/modules/system/system.module on line 2120, when accessing admin/commerce/products/add-bulk.

Commented out that line on system.module and could access the page, but got:

Notice: Undefined index: mlid in system_admin_menu_block() (line 2123 of /home/web/modules/system/system.module).
Notice: Undefined index: mlid in system_admin_menu_block() (line 2134 of /home/web/modules/system/system.module).
Notice: Undefined index: menu_name in system_admin_menu_block() (line 2135 of /home/web/modules/system/system.module).
Notice: Undefined index: mlid in system_admin_menu_block() (line 2154 of /home/web/modules/system/system.module).

And the page reads:

None of the product types you have created so far are available for bulk creation. In order to be avalable for bulk creation, a product type must have at least one field that supports it, such as a list field. Go to the manage product types page to add fields to your product types.

This was not happening with 1.x, and I could see the form correctly, thus 1.x recognises the fields on the product type, but 2.x not.