Download Firmware NEC ND-2500A K0P2 Double Layer

There is a topic on The Firmware Page too find stating that it is possible to convert the NEC ND-2500 DVD burner to an ND-2510 double layer burner. The download contains three different firmware versions: the first file contains the original ND-2510 software. The other two files can flash an ND-2100 to a region-free ND-2500, with or without rip lock, which removes the limited writing speed of single and double layer DVD media:

2100@2500 allows the firmware to work on a 2100A drive if you have one.

Rip Lock removes the speed locks on single and dual layer DVD-ROM discs
with a VIDEO_TS directory.

RPC1 removes region state handling commands and checks.