There are and have been for a while now systems that can dispatch group elevators to the "uneven/odd floors" of any building such as you describe. Actually, with the micro processor based systems of the last 30 years, it's been possible. Any of the major companies can engineer software today to meet your buildings needs exactly. There are also secondary or after market manufacturers who can provide a quality product for any building design. Motion Control Engineering (mceinc.com), Computerized Elevator Control Corp. (swiftcec.com) are two companies worth mentioning.
Hope this helps.
*Now be sure to suggest to your "client" to upgrade their system even if the payback is 10 to 12 years in energy savings.
At least they'll have a system that will perform well for the next 30 years or more.
