Alright, so I've had a look.
I think the crux of the issue is you have created all windows, including your windows with tab strips as "main windows". It's quite hard to tell in Designer in V8, when you right click to create it shows the "docked windows" with a stripe right the way across the top, but once created it looks the same as the symbol for a main window (two dots top left).
You should not be using scripting with the open/swap options. Double click the component (tab strip) and this opens the tab strip customizer. I see you've already been in here, as some of the config is there. However, some are going to "Tab 3" etc, not "Main Windows/Roll Stand Temps" etc.
So not sure if you only did a partial export, or if you just haven't created all windows yet. Another tip, place a label on each window, and enter the text as what the window is supposed to be displaying. That way, when you are changing through them for testing, you can see if they have successfully opened or not. For future help, a full GWBK (Gateway backup), may be more useful, so long as there is no confidential information in the project. To do this, go to the gateway in your web browser, config, backup/restore. Just comment what version you are using, as 8.1.25 cannot be restored into 8.1.20 etc.
As suggested, you may want to download the full version onto another laptop, or a VM, and create a project with a template and see how it is setup. The one you want to select is "Vision Tab Nav". This uses the same tab strip component you are.