Registration codes are often version-specific. If you bought a license for Zulu v4.0, it might not work on v6.0. Always download the version that matches your purchase.
For more help with registration or technical glitches, visit the Zulu DJ Software Support Page comparison of features Zulu Dj Mixing Software Registration Code
The full version of Zulu DJ is $49. That is roughly the cost of two pizzas. For that, you get: Registration codes are often version-specific