Small bug report...
Activating the "Segments with letter" filter makes the Segments grid source acting strangely. It shows parts of the hidden codes (bold, and so on) and highlights the source. Deactivating the filter doesn't solve the problem (but reopening the project does).
Can you submit a support ticket with a .ctp package file attached? If this is a regular CT project, create the package via the menu Project > Export and exchange > To package... .