The serial number Elbox wants is hand written on the install CD ~ the MMCD. their major products will have printed tags which appear to be serial numbers. With the CD's serial number you can get somewhat better (although almost nil) service and accesses to newer device drivers. Elbox got angry that folks copied their hardware (Spider USB card) and is very restrictive in some respects. Keep in mind that while Amiga OS 4.1 supports their PCI board, they wrote all new drivers including PCI cards that Elbox doesn't support
Does any of this help? End result, find your serial number or start taking scans and photos of your hardware to prove its original. This may get you the drivers, but only rarely do they give any support for their products.