How to find the ngen.exe for framework 1.1
This can be done very easily using a file search from the Search page. The name of the search is actually an installer public property so if it finds the file it will
contain the exact path for it, otherwise it will be an empty string.
- How to use the result to ngen my DLL
You will need to read the value of public property(name of the search) using a special API. Here is an example
- How I can find the DLL name in the GAC (like: "Syncfusion.Core, Version=4.401.0.51, Culture=neutral, PublicKeyToken=632609b4d040f6b4" )
Since this is not done by a simply file search you can try using another custom action that retrieves all this information from the registry or any other places where it is kept.
You will need to consult MSDN in order to find out more about how the OS stores all this information.