Thanks for your patience here, Felix.
This is actually already possible and the information can be found in our knowledgebase (apologies we didn’t link you to this earlier!) – in essence the trick is to use so-called “pipe separated” values.
Let’s suppose we have a custom checkbox field for which any of the following are acceptable values:
- Anchovies
- Cheese
- Jalapenos
- Meatballs
- Pepperoni
Within your CSV data, you can nominate two or more of these for each event using this sort of syntax:
Anchovies|Jalapenos|Pepperoni
Does that answer your question?