Hi,
Here is few suggestions to improve this application:
1. Pagination. With "Next" and "previous" links there is hard to navigate throw hundreds of customers.
2. Direct link to "Check record" for client when pushing ID in "Pending orders" section (similar to MaxMind "Re-run fraud check" link).
3. When submitting record, system brings me back to page 1 instead of previous page. Try it, very annoying.
4. Sorting options would be awesome. By name, by signup date, by country.
5. More Ajax, less page-to-page jumping
Keep a good work!