How to custom sort Marketpress Product List order via Shortcode

Is there any way to custom sort the order of a Products List using the mp_list_products shortcode variables?

I only notice order_by and order as options for sorting the Products List. But if we need to present certain products in a specific order, it seems like the only solution is to use multiple shortcodes for single products in the desired order.

If there is no way to currently create a custom-sorted Products List, please consider this a feature request and feel free to move this topic.

One suggestion might be to add a order_custom variable with the option to list products by ID in the desired order.

Example: order_custom="9,12,4,3,1" would list products with those IDs in that order (9,12,4,3,1). Make sense?

Or... perhaps just add the ability to list IDs in the order variable, instead of just ASC or DESC.

Example: order="9,12,4,3,1" would list products with those IDs in that order (9,12,4,3,1).

So, for now, is the only way to accomplish this by using individual shortcodes for single products?

Thanks in advance for any help!