Hey @sonspot,
Truthfully, I have no suggestion here. Reading the WPML website they say “Every theme or plugin that uses WordPress API runs multilingual with WPML” right on their homepage; however, the fact that you are saying that OpenTickets has problems with it makes this statement completely untrue, since we use almost exclusively the WordPress APIs.
You do not go into detail here about what works and what does not work, but I imagine that probably some of it works and some of it does not work. Because you are a Seating extension customer, we could probably spend some time working with you to find out what parts of the system are not working with WPML. We would also need to figure out why, and assess if making it compatible is a viable option. We would not know until further investigation is conducted though. You will need to hook up with us in Support Desk though.
I think on Monday you may have sent in a Support Desk ticket about this, because I was asked a couple offhand questions about a similar topic while in the office. I will check with the guy who handles those requests, and if it was for this exact issue, I will have him get with you to establish a method for us to do a further investigation.
Loushou