I've started making a payout calculator in Google Sheets. I've managed to fix the rounding error by adding or removing the difference from first place. Currently it will input buy-ins, rebuys and add-ons and allow you to enter a different amount of money for each one. It will keep the number of players the same based on the number of initial buy-ins. It's also capped at 50 players but that's easy enough to scale.
Once my V1 is done I'll share it here for anyone to play with that wants to.
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