Using wx.html.HtmlHelpController()

I am trying to use the HTML help controller in one of my projects (wxPython latest Phoenix running under Mint 20.3) and I am having difficulties figuring out what sort of input help file types the ctor accepts.
Currently, it seem it will accept a *.hhp file, but the only way I know of creating one of those is to decompile an existing *.CHM file.

My code looks like:

def InitHelp(self):
        self.help = wx.html.HtmlHelpController()
        #helpFile = "/home/arnold/Public/pkg/python/wxPython/wpSkAui/wpSkAuiHelp/htb/wpSkAuiHelp.zip"
        helpFile = "/home/arnold/Public/pkg/python/wxPython/wpSkAui/wpSkAuiHelp/htb/wxSkAuiHelp.hhp"
        self.m_textCtrlLog.AppendText( helpFile + "\n" )
        if os.path.exists(str(helpFile)):
            try:
                self.help.AddBook( helpFile )
            except:
                print( "Error")
                self.m_textCtrlLog.AppendText( "Exception: Could not load :" + helpFile + "\n" )
        else:
            print( "File does not exist:" + helpFile )
            self.m_textCtrlLog.AppendText( "File: " + helpFile + " does not exist\n" )

The documentation says:

AddBook<big>(</big>*book* <big>)</big>
Adds new book.
book is URL (not filename!) of HTML help project (hhp) or ZIP file that contains arbitrary number of .hhp projects (this zip file can have either .zip or .htb extension, htb stands for “html book”).
Returns success.
**Parameters:**
* book (string)
**Returns:**
bool

Evidently the code does not implement what the documentation says -
I have tried to use a newly generated HTB file with the appropriate content, either directly or renamed to have a zip extension.
Either case displays a bare & empty help dialog.

If I do use a HHP file from a decompiled CHM file, the help dialog will display the contents of the old CHM.
Any help, comments or suggestions will be much appreciated
Arnold

There is an example in the wxWidgets source tree that includes some basic help source files, and also some more details about the content and structure of the help files in their documentation.

Meanwhile, I have played with my wxPython test project and Jutoh to generate a new HTB file.
Passing the full path & filename for this HTB file to the help controller, produces no error, but displays a completely empty help dialog.
Same thing if I rename the HTB extension to ZIP.
If I extract the contents of the newly compiled HTB file - by default the files will end up in a directory named wpSkAuiHelp.htb_FILES - and pass the full path and file name for the HHP file, I do get the data I expect to see in the help dialog.

The ‘look’ of the dialog - mainly the icons and the navigation pane - is quite different from the helpview example from even the old wxWidgets 3.0.2 and looks very sad/bad, though it is usable to a point.

If I was working under Windows & Visual Studio I’d be tempted to follow the code to the source, but with wxPython, at this stage, that seems out of the question.

Curiously enough, when I search for “HTB viewer Linux” or equivalent criteria, the only example for opening HTB files which seems to come up is Audacity. But when I install it and download the local help files, it turns out that the developers chose not to use the wxWidgets based HTML help system, but instead to go directly to the default browser with a file based URL to the main index file. Possibly for legacy reason, but the search results are both misleading and discouraging

Final questions:
how can I go about fixing this or is there a work around - missing zip handler? and where could/should I have tested for which error return?
or do I need to go the Audacity way??