Never going to happen in Oz, far too many rocks and hard places for little johnny to hurt himself/herself/themselves, needs more cotton wool to satisfy OHnS. My god that poor victim is exiting the slide onto a slope, she could turn an ankle. Oh the horror...

It does work with both circle and polygon the same way, make sure you are doing as instructed.

Select the tool and before doing anything type 8 and hit enter to confirm, then draw your circle or polygon and it will have 8 segments/sides.
Note: this method will set the default for that tool to 8, so each circle or polygon will have 8 segments until you change it or start a new instance of Sketchup.

The other option if you want to retain the default 24 or 6 and just draw one C/P with a different number, Select the tool and draw your shape, then type 8s and hit enter to confirm and the shape will change to 8 segments.

Have a look here.
https://sketchucation.com/resources/tutorials/beginner/315-edges-bleeding-through-geometry

If you are wanting to do a lot of that sort of thing you may find SUbD works for you.

I've done a quick bit using your model. Here I just used a few straight lines to create a path for the beziers. This helps to create a smooth transition.

My guess would be that your edges don't have corresponding vertices. If the edges are too different it can force overlaps. I'd also scale the middle profile somewhat as shown in the tut.
It can also be easier, or more controllable, if you use an arc to join the profiles.

I haven't tried to make this nice and smooth, it's just thrown together to show another technique.

@gus r said:

I can get the fillet to loft but it just doesn't connect with the two main elements.

I'm unsure what you mean by this. At the most basic level you do understand that the lofted part is a separate group and needs to be exploded to connect with the other parts.
If that's not the issue could you perhaps explain a little what the problem really is.

@ntxdave said:

I also tried to set it do double wide but it would not allow me to do it in that position. Am I missing something?

No you aren't missing something, the toolbar won't do double wide when docked, even though the Large Toolset does. It has been a complaint for many years. And you can't put the large toolset across the top.
Far be it for us to question the design gods of the UI, they obviously know something we don't.

@ntxdave said:

BTW, is there a way to add the bottom view to a toolbar?

Not in the older versions, but you can make a keyboard shortcut.

@box said:

That Icon is Delete from the 'Standard' toolbar.

@ntxdave said:

Thanks for the link but I could not find a toolbar that had the delete icon.

That Icon is Delete from the 'Standard' toolbar.
This thread has a gif showing how to make a custom toolbar from about 9 years ago.
https://sketchucation.com/forums/viewtopic.php?f=15&t=59701&hilit=+toolbar#p543863

It's worth noting that this Trim function is broken in 2023, you have to reselect the tool each time.
But I suspect you aren't working with 2023 anyway.

Use Trim.

Nested groups are not solids, so your group of groups cannot work with solid tools. You must either explode the log groups into the parent group or explode the parent group and do multiple subtractions, one log at a time.
You also have an extra couple of misaligned logs at the bottom.

So here in this gif, I delete the extra log, explode the log groups creating a single solid then subtract the 'hole'. You could regroup your logs after, loose to groups would do it in a click or two.

Some people have had success with working around this issue by making sure Enable Scene Transitions is ticked in Model Info/Animation.

Liam there are no 'layers' in Sketchup anymore they have been called 'Tags' for several versions now.
They behave the same way, only the name has been changed.
Tags will be found in the default tray on windows.

You can't make something unique if it is the only one, it is already unique.

That is there so you can drag and drop materials from folder to folder.
There is a little arrow and cross symbol top right with the Help info 'Display the secondary selection pane'.
Just click it and it will go away.

Scroll back up to the image Dave posted, look at the waterfall and how it drops into a 'canal' now follow the canal to see where the water goes.
Now model that path.

No need to apologise, just google search escher and look.
I can't imagine working in any sort of imaged based industry and not be aware of M.C.Escher.
Do the search and click the images button, then do the reading.