Close and reopen the application after installation. If it still doesn’t appear, restart your computer. Some older creative software requires a system cache reset.
Kruti Tamil 100 is a classic, non-Unicode, anchor-based Tamil font. It belongs to the larger "Kruti Dev" family—a series of popular Indian language fonts (Hindi, Marathi, Gujarati, Tamil, etc.) that became the industry standard for DTP in the 1990s and early 2000s.