I just resolved my issue. I have used the "System Search" under "Behavior and logic" to achieve this Steps for resolution are as follows
Step 1: Open "System Search"
Step 2: Right Click on one of the rows and click "Add" or press "Insert" button on the keyboard.
Step 3: Click next on the "System Search Wizard"
Step 4: Select "Registry Entry" from the dropdown and click next
Step 5: Select the "Registry root".
Step 6: Provide the appropriate path for the Registry Key. For example: SOFTWARE\Microsoft\SQLXML 3.0\Setup
Step 7: Select Registry value. Here add the name of the registry key you want to compare. For example: patchLevel
Step 8: Click next. Now select the property which will store the registry key value. For this make sure you have already created one property for holding registry key value. In our case let us assume the property name is IS_SQLXML_INSTALLED. In additional option, select store the value in property and use property in install condition. This option will automatically search for the registry key at the installation.
Step 9: Click on the finish button. As soon as you click finish button a dialog box will condition builder pop-up will appear. Provide the appropriate condition. For example for checking if the SQLXML component is installed, condition will be IS_SQLXML_INSTALLED = "3.0"
Build your installer and run. If in case your want to play with different conditions. Make sure you delete the condition from the launch condition table.
Deleting a "System Search" row will not delete the entry from Launch Condition table. (Additional Tools -> Direct Editor -> launch Condition)
