I would check with support though how they handle 100% donations, because itch.io's system does this:
- Let's say you receive $1 excluding tax (the tax is collected and paid to revenue authorities, it doesn't appear on our accounts)
- From the $1 they take the itch.io cut first, and then deduct the costs.
- For example, if you give itch.io 10%. They take 10% of $1 (10c), then you pay about 30c payment processor fees and you end up 60 cents.
- If they apply the same calculation to a 100% take, you could end up with a negative balance (the payment processor fees) where you're expecting to end up with a zero balance.