I suspect you need to reinstall this extension [and perhaps some others?]
Extensions don't automatically 'port' over from an earlier version of SketchUp when you install a newer one -
although v2025 does have a new extension to let you do that -
but it's not 100% foolproof, and reinstalling them manually does let you do some tidying up and housekeeping, to keep your extensions 'lean-and-mean'...

Please read its usage notes.
You must have just one section-plane selected.
The right-click menu then offers you the tool with options as appropriate.
It does not appear in any other menus or have a toolbar...
You need to read its usage notes to understand how it works and to get the results that suit you...

@atelierpaar

Basic 3dText is not 'editable', you need an extension like this -
https://sketchucation.com/pluginstore?pln=tt_texteditor

Feel free to cannibalize parts of my ImageTrimmer, which smooths jaggedness...

You pass the edges' collected vertex points, and set an epsilon factor... thus.

      ### epsilon is a float perhaps < 0.2 
      ### perhaps it's set by the user ? experiment for best default...
      ### the vertices are collected from the current outline[s]
      points = vertices.collect{|v| v.position }
      simplified_curve = douglas_peucker(points, epsilon) ### might return []
      simplified_curve << simplified_curve[0] if simplified_curve[0]  ### so it 'loops'
      edges = some_entities.add_curve(simplified_curve) if simplified_curve[0]
      ### sort out edges' faces, hide edges etc as desired

the 'douglas_peucker()' method is this...

  ### http://en.wikipedia.org/wiki/Ramer-Douglas-Peucker_algorithm
  ### http://en.wiki.mcneel.com/default.aspx/McNeel/
                                        PolylineSimplification.html
  ###
  def douglas_peucker(points, epsilon)
    ###
    return points if points.length < 3
    ### Find the point with the maximum distance
    dmax = 0
    index = 0
    line = [points.first,  points.last]
    1.upto(points.length - 2) { |i|
       d = points[i].distance_to_line(line)
       if d > dmax
         index = i
         dmax = d
       end
    }
    ### If max distance is greater than epsilon, recursively simplify
    result = []
    if dmax >= epsilon
      ### Recursive call
      recResults1 = ImageTrimmer.douglas_peucker(points[0..index], epsilon)
      recResults2 = ImageTrimmer.douglas_peucker(points[index...points.length], epsilon)
      ### Build the result list
      result = recResults1[0...-1] + recResults2
    else
      result = [points.first, points.last]
    end#if
    ###
    return result
    ###
  end #def

This is worthy successor to my oldie ImageTrimmer - much faster and with better in-built toolset...
Can't wait to try it !

@lamngoaison

The linked post contains a ZIP file posted a few days ago
link
Which can be converted to an RBZ by changing its filetype suffix.
It worked in v2024, so should also work in v2025 ?

@masmoosa
What extension are you referring to ?
There's insufficient info for us to help you.
Please give us a clear description of what you are trying to do, and what problems you are experiencing...

Have you actually installed the app properly ?
Running it from the downloaded app's installer can work, but it can also have weird side-effects like this...

@GavinG

When you say you 'migrated' the plugins, did you install them from scratch using the ExtensionStore³ dialog, or from RBZs downloaded from the PluginStore ?
What are the 'warning messages' ? Knowing these would be most helpful...

PS: Don't give your email address in a public forum, some spam-bot may have already scraped it up. I've obfuscated it a bit, but you might want to do it yourself.
Conversations through forum posts are the most effective, Chats [PMs] can be used if you are providing confidential stuff, emails are a last resort - for licensing problems etc...

Things like forgotten toolbars etc are a sign that preferences aren't getting saved - usually because preference files don't have the correct permissions.
This is usually because SketchUp wasn't installed properly [on Windows]. This can be fixed without having to reinstall SketchUp, do this...
Close SketchUp
Find its installer exe file - usually in your Downloads folder [or get another copy]
Select that exe file's icon, right-click > context-menu > Run as administrator...
In the dialog which opens choose 'Repair'.
When it's done restart SketchUp and arrange your toolbars as desired.
Close SketchUp.
Open SketchUp - is there any improvement is the remembering of preferences ?

Other things like installed extensions should be unaffected.

Double-clicking an installer's exe file to 'Run' it is not the same as doing it as outlined above - even if your user-account has admin-powers...

It is not completely hardcoded.
When SketchUp installs it makes a set of default folders e.g.
C:\ProgramData\SketchUp\SketchUp 2024\SketchUp\Materials
is one of those, containing the materials in subfolders that you no longer want.
If you delete it completely or rename it - say Materials!
Then it shouldn't load next time.
However, if you reinstall or repair v2024 it will be recreated.
BUT when you run SketchUp it is recreated As Materials BUT it is an empty folder.
You can also delete selected subfolders, if you still want some of the default materials to be available.

The latest version works fine for me too, across all newer SketchUp versions.
What is your exact issue ?

So that error seems to relate to a missing directory or file.
You need to wait for the author to resolve this .
Sorry.

You need to install it into v2025 from the RBZ - with errors.
Then close SketchUp and find the RB file in your Plugins folder, open it it with Notepad++.exe and do the edit as outlined above...
The installed file is C:/Users/YOURUSERNAME/AppData/Roaming/SketchUp/SketchUp 2025/SketchUp/Plugins/ams_SmoothZoom/extension_manager.rb

@kurdoc69
Read my reply above yours, it outlines how to do a manual fix on the RB file, until the author responds.

Until there's a fix available, because the error is in a RB file you can edit it with a plain-text editor like Notepad++.exe
Find where it says File.exists? and change it to File.exist?
Both method coexisted for ever and were equivalent to each other, but in >=v2024 someone chose to deprecate the original correct-English sounding version, and cause authors issues.
After you save that edit restart SketchUp to see if that fixed it...

It is 'clever' but...
Sorry, I have a few issues...
No handrail[s] or side balustrade - a potential death-trap, or at least severe injury risk to kids, the elderly, or anyone who's had a few life-enhancing drinks of other substances.
The gaps in the risers - a potential death-trap, or at least severe injury risk to kids.
The treads do no overlap by about 1"/25mm to form a safe 'nosing'.
The remaining thickness of the cut relatively thin plywood 'stringer' [to the outside of the flight] is quite small and it would need only one to crack/break to cause a catastrophic failure and collapse.
In addition - the first floor seems to have no fire-resistant construction, and also what stops the whole thing 'unfolding' from the wall and 'dropping', in a way that might endanger someone e.g. a kid ?
So you won't be seeing me making one like this anytime soon...

@miguelbarbosa5
A clearer explanation would help us to help you !

The LibFredo6_all_defaults.dat can have incorrect permissions if SketchUp was installed incorrectly [i.e. not using 'Run as administrator']
Although running it again 'as administrator' and choosing 'Repair' should fix most permission issues, some remain - especially with extensions saved files/folders.
Deleting the the LibFredo6_all_defaults.dat while SketchUp is closed should work as SketchUp will recreate it with the correct permissions when it next runs.

I suspect the unexpected user name ending ~1 is because your umlaut containing name is there under the surface.
Renaming it FJS doesn't change it's underlying name ?
Can your tech guy help sort out your user-account name, without any accented characters etc [as prohibited by Microsoft, but Windows lets them slip through]

Have you tried downloading the installer exe again from SketchUp or your local supplier ?
There are two versions one is a larger file containing everything needed, the other downloads some components from the web...
The larger one is the safer option...

Depending where it fails there might still be a MSI file extracted with all of the needed files, even if the full installation stalled.
If you find that you can try running it...
e.g. C:\Users\YOURUSERNAME\AppDataLocal\Downloaded Installations\SketchUp 2024\SketchUp\SketchUp 2024.msi
Try the FJS and perhaps the FJSCHS~1 user-name...