Firmware upgrade of DVD in G5


Hi I have an ancient G5 that I still use. I have just tried to burn a DVD dual layer on the internal Pioneer DVR109 drive which failed (twice). I also tried to burn on a DL disc where the data didn't exceed 4.7 GB and that worked fine.
I assume that the drive needs a firmware update but how do I do that.
I have found the update on Pioneers homepage but it's a windows file and shouldn´t there be some kind of program to get it installed.
The last to firmware upgrades had something to do with DL discs so it just may work.