Guillaume,
If you build a DLL with CVI 7.0 you need to have the CVI run-time version 7.0 (or higher) wherever you load the DLL. The CVI run-time is backwards compatible, and it's free, so there's nothing stopping you from installing it wherever you need to use the DLL.
You also mentioned .obj and .lib files. These files are not tied to any version of the CVI run-time. If your purpose is to take an .obj or .lib that was built with CVI 7.0 and link it into a project in CVI 5.0, you can do so as long as they don't reference any functions that were introduced after CVI 5.0.
Hopefully this made sense 🙂
Luis
NI
