Problems with code synchronization

[franck]

I am new with code synchronization in EA. Here is what I want to do:
1. Write some C code
2. Import it within EA
3. Modify my C code (not in EA) and periodically synchronize it within EA to bring changes in my EA model.

I am able to do all this right, but I have a problem when I change any parameter of an existing function. In that case, when I syncrhonize, I loose all the text I entered in the "Operation Behavior" property, just like if EA deleted by previous Operation and completely replaced it with a fresh new one.

What I am doing wrong, or how to prevent loosing this information?

Thanks
Franck