Bus input/output in c s-function and rapid accelerator mode

Hello,

I am trying to develop an s-function with a bus signal as output. I managed to do that using the sfunction builder. In normal mode everything works but if I try external mode or rapid accelerator mode I get the following error:

 The model that you are trying to run in External mode does not match the application running on your target. Rebuild the model, run it on your target, and start External mode simulation again.

I have the same error also running the example sfbuilder_bususage. Any hint? Thanks in advance.