For those regarded like me, you set the amounts by separating the values with a comma, as stated, in the text pop up field when long pressing the ⚡
Amethyst V0.17.10: UI Improvements to set custom zaps
Download: https://github.com/vitorpamplona/amethyst/releases/download/v0.17.10/app-release-v0.17.10.apk
For those regarded like me, you set the amounts by separating the values with a comma, as stated, in the text pop up field when long pressing the ⚡
Oh wait it just got better.