First, you've customised all the UI, and that allows the game to be its own little world, and not just another game under Ren'Py.
Second, as a non-native speaker, I had to use the dictionary several times (not for crab parts, I'm a biologist :) ). But that's good, it shows that you have ambition for your reader by offering something that isn't generic!
And, good luck at work.