I would use the default helix ultimate template, no extra templates.
In order to see the problem exactly, I will send you the information required for entry.
You can see in the editor that the visibility of the button is turned off on the first slide, but it is still there, visible on the page.
(The visibility switch works for the main slide elements)
My second suggestion is that for the individual elements where you can insert text, images, buttons,
for images, I would recommend a vertical position switch. You can see in the example why this would be important from the point of view of design.
I am currently solving this problem with an extra css that can be inserted here.
(And here the related css question arises. I had to separately decide that these content parts should be in the flex class,
because the positions can be handled much more easily, perhaps it would be worthwhile to consider introducing this at the factory)
Thank you for your attention!