For the interaction part, we wanted to use the TUIO/CCV image API with our Unity project. This worked fine until we tried to build the project and run the exe file, and the touch input wouldn't work at all. We really wanted to fix this since we wasn't interested in being forced to run the program through the Unity editor.
We tried several solutions. For exampe, we deactivated the firewall since we initally thought that it would occupy the same port as TUIO. However, this didn't solve anything. We also tried to implement other TUIO-supported API:s. One of these was the TouchScript API, which was supposed to work with TUIO, but it didn't work either.
It was very hard to find any documentation on TUIO and Unity, and it was even harder to find a solution to the Unity build problem. After some extensive Google sessions, we found only one (!) post that even mentioned this problem (read it here). The solution there was to do modifications in the actual TUIO API (or try to implement another modified TUIO protocol). At this point, we almost gave up since it seemed impossible to solve this problem.
However, we discovered that the error message in the log file from the build wasn't telling us everything. We did some googling on this specific error, which lead us to another problem: some Unity DLL-files, that the TUIO API needed in order to work, didn't follow from the Unity editor to the build library. We added these files, and it worked! We could finally use TUIO in a Unity build.