Error 0x346402 when writing large amount of data to Neverwinter Nights save

[Cirosan]

To import some player-made content into the Switch port of NWN, I need to write a relatively large amount of data into the save: just over 5gb. I've tried cutting it down to just over 1gb, but the error stays the same. Is this an issue with NWN's save file size limit, or with Checkpoint itself? If it's the former, do you have any insight as to how the game's save file size limit could be increased? Thank you for your time and an immensely useful piece of software.