I worked for a very very similar project. It was not so fundementally twisted and evil - we had multiple tables, all named like t1004, t12 etc. It was a smaller version of this monster. But the database had metadata and data, generic string fields, and so on. Speedy Gonzales performance, with queries not fitting in the join limit of the database engine.
And here too the original creators had managed to retain the rights to sell the "product" (haha) to other companies.
The trio who was behind all this evil are still in the industry after being sacked after 2 years of "development". Watch out.
Its memories are still haunting me, as it was my first real job in the industry.
Oh My God.