VCL Studio has some major usability issues. The syntax highlighting and search and replace in particular are prone to error and may cause VCL studio to crash. CIT allows users to make use of an external text editor. Users may do this by placing VCL files on disk, external to the CIT project, and editing them using a text editor of their choice. This also allows easier version control of the file. The only VCL which should be saved in the project should be a file which references the external VCL files like so:

   include "<path to VCL file> "

Note that the above path string is interpreted according to C-string rules so "\" needs to be escaped with a second "\".