I talked with the Swiss responsibles today. While it has been relatively easy to performance-tune a car here unless you don't exceed 20% more power over stock this has changed now.
Expect to pay 7k - 10k US$ to get your tune homologated. If you don't, you will not have any insurance at all, you drive an illegal car.
While I like to live here, this new homologation is really hefty. E.g. 12k for a SC kit plus 10k for the paperwork, this sucks.