Passing parameter to .ini file

I have added a page in the install script to enter some text input by the user. For this I have used a .ini file. Is there any way to pass parameter to the .ini file, so that the text label can be customized based on the parameter value?

After extracting the ini file, simply write to it (using the MUI macros or NSIS's INI functions) before you show the custom page.

But using InstallOptions is not recommended. It is old, slow and very very messy. I strongly suggest you use nsDialogs instead.