If your project's Lua code relies on C functions in a dynamically linked library, you will need to make sure that the interactive engine can find and load your dynamic library at runtime.

In order to launch your content from the interactive editor using either the Test Level or Run Project methods, you will need to make your dynamic library available to the instance of the engine that the editor runs internally.

The easiest way to do this is to place your dynamic library in the engine's directory within your 3ds Max Interactive installation folder. For example,

C:\Program Files\Autodesk\ Interactive\<version>\engine\win64\dev

You could put it in a sub-directory within this location, as long as you add the relative path to the require call that loads the library in your project's Lua script.

When you deploy your project, you'll also need to copy your dynamic library to the final output folder.

For Windows targets, you can automate this task by editing the package.manifest file that you'll find within the engine directory in your 3ds Max Interactive installation folder. Add the relative path and filename of your library to the list of files in this manifest, and save your changes. From now on, when you deploy your app, your dynamic library will automatically be copied to the same relative path in your app's deployment directory.