Problem getting custom dialog to compile

I am using HM NIS Edit to produce a simple dialog comprised of two text boxes and two labels. I have simply been trying to get NSIS to display the dialog box. Then I have to get the information from the two text boxes. This is getting ridiculous. What should be easy, is obtuse. References to script file segments that appear in prior posts aren't present in the files produced by HM NIS Editor, as demonstrated by the difference between what the "oninit" reference here suggests should be present:



and what was actually in the script file produced by HM NIS Editor, which is attached. (In truth, I'm not sure I want the serial number dialog to be first on the roster of screens, even before the "welcome" screen.) Does anyone have any idea how to get the "UserSerialNumberDialog" to display? Any idea how to control where its shows up in the order of screens that are displayed. How does one actually get data from the text boxes on a custom dialog, and where does one put the code that gets that text?

Thanks for any straightforward answers to these questions.

HM NIS Edit simply helps you create your custom page(s) in a graphical user interface, this means that you don't have to edit the ini manually, instead you add controls on the gui and HM NIS Edit makes the rest of the job regarding to the ini. The rest is all up to you, to add the custom page in the script, to show it by the proper function and take the actions from it by the proper leave function.
You may want to read the InstallOptions documentation for more info and examine the included examples.

Just edited a little your script, check the differences.
Don't forget that the ini must have the same name as refered in
Function .onInit
;Extract InstallOptions INI files
!insertmacro MUI_INSTALLOPTIONS_EXTRACT

and also in
Function UserSerialNumberDialog
# Display the page.
!insertmacro MUI_INSTALLOPTIONS_DISPLAY