I get this error on the administration side of the store, though it seems to work fine in the front:

Notice: Undefined index: replace_taxonomy_field in commerce_taxonomy_field_product_attribute_form_field_ui_field_edit_form_alter() (line 28 of /var/www/drupal/sites/all/modules/contrib/commerce_taxonomy_field_product_attribute/commerce_taxonomy_field_product_attribute.module). Backtrace:
commerce_taxonomy_field_product_attribute_form_field_ui_field_edit_form_alter(Array, Array, 'field_ui_field_edit_form') module.inc:1018
drupal_alter(Array, Array, Array, 'field_ui_field_edit_form') form.inc:1058
drupal_prepare_form('field_ui_field_edit_form', Array, Array) form.inc:332
drupal_build_form('field_ui_field_edit_form', Array) form.inc:123
drupal_get_form('field_ui_field_edit_form', Array) 
call_user_func_array('drupal_get_form', Array) menu.inc:517
menu_execute_active_handler() index.php:21