We had a problem with the module: it didn't save properly which domein/store was used when ordering. It did show the panel @ /admin/store/orders/x, but it always stated the main domain was used, even when it was not.

The table uc_domain_orders contains an order_id column, which is mediumint. I noticed it didn't contain any valid order-id's. Our order-id's contains 8 digits. I made the column a bigint instead of a mediumint and the problem was solved. Maybe it should be bigint anyway?