No, there shouldn't be any problems if the flashing of the BIOS is successful.
Generally, upgrading of BIOS should only be done if there were some issues with the system, otherwise the BIOS should be left alone.
Downgrading BIOS is not usually done unless issues appear after the upgrading BIOS. As it seems in this case here, downgrading the BIOS is probably the best way to go to help with memory issues.