Adding Library Files to Projects
Most Tibbo libraries are supplied as a pair of files — a .tbs file with all the code and a .tbh header file with declarations. Both must be added to your project.
Reminder: library files you are adding always come from the selected library set. More information can be found in Adding Files, Understanding Base Locations.
Library files are not copied into your project's directory; they are just "referenced." Notice also how they appear in the Libraries tree node of the project tree. Added library files are initially locked for editing. This is why you will see their file names in gray, with the "lib, lock" label printed next to them as well.
You can unlock the files (by right-clicking on the file in the tree and selecting Unlock), but this is not recommended.
Do not change the code in the library files. If you feel that a certain library doesn't fully answer your needs and requires modifications, copy the library files into your project's directory, add these files as the project files and then modify the code in the "derivative" files.