You can register your Keil licence using following 2 methods:
From Keil MicroVision IDE:
1. Go to Uv4.exe (that gets installer along with PSoC Creator) in C:\Program Files\Cypress\PSoC Creator\2.0\PSoC Creator\import\keil\pk51\9.03\UV4\Uv4.exe.
2. Click on File->Licence Management. Add your LIC code here and Click on "Add LIC". The licence gets added.
By renaming "_TOOLS.INI"
1. Rename "_Tools.ini" to "Tools.ini" in the path "C:\Program Files\Cypress\PSoC Creator\2.0\PSoC Creator\import\keil\pk51\9.03"
2. Now add your LIC code in PSoC Creator, Help->Register->Keil and click on "Add LIC". The licence gets added.