Please read and let me know if i'm doing this right.

i have the Optorite DD0203 CD/DVD RW. i tried to update to firmware 2.50 and this is how i done it i create a windows XP MS-DOS bottable disk.
step 2 i download the 2.50 firmware from the optorite site, extract the file to a floppy. now i restart my pc with the boot disk once it take me to a dos prompt I put in the disk with the firmware this is what i type

A;\dvflash.exe dv2.bin \f once i do that then i select the drive and the update start 1.writing data to the drive 2.varerifying data now those 2 step go 100% ok the third step is updating verison BIOS this step goes only to 33% and nothing happen i even left the computer about 2 to 5 hours but nothing, how do i complete a update? please help thanks for reading