Thanks for the response. Just to insure everyone is on the same page, I did
install Beta v1.01.42, announced on Jul 23, 2026 by Sandrasy:

https://forums.matrixgames.com/viewtopic.php?t=417555

and the Open Existing Design bug in the DLC Ship Designer is still non-functional.

I appreciate that ...

Dear RedeyeFlight,

I completely concur. Load Custom Ship button in the DLC/Ship Designer
is non-functional. The freaking Ship Designer saves custom designs to
one location -- but the Load Custom Ship button is trying to load
from God knows where. It's not just us -- this has been an ongoing ...

OMG!!!!
My bad!!! I see what is going on.

Under your Documents > My Games > Rule the Waves 3 >
you have two (2) folders (!)
One folder is "Custom files"
The other folder is "Custom Files"

Only the ........\Documents\My Games\Rule the Waves 3\Custom Files\ is legit.
I recommend copying the scenario ...

You should be in good shape now. Your scenario was placed under the Documents tree into Custom files.
To play it, press the Play Scenario button on your Main Screen. You'll have a choice of 3 tabs:
Scenario, Custom Scenario, Saved Game.
Choose the Custom Scenario tab, this should point directly to ...

I can confirm that my Ship Designer--Custom button does "File not found". In the folder:
C:\Users\dmilb\Documents\My Games\Rule the Waves 3\Custom Files
I do have 5 .sdf's and 16 folders holding submitted scenarios.
I can reach them by using the Stock button, and then the GUI window to maneuver over ...

I am running 1.01.38 with the DLC. I also keep my RTW3 folder on my D: drive.

When I open the Scenario editor, and press "Load scenario button", it should open
a mini-window asking for Stock or Custom.

If you press Stock, it will open the "Scenarios" folder in your RTW3 install folder.
(on ...

I'm just a regular gamer, not a dev. I can confirm that this issue is not fixed.

I am running V. 1.01.38 in Win11Pro.
In the Ship design window, I click on the file folder icon in the upper center of screen that has a "Open existing design" tooltip. This generates a small window labeled "Confirm ...

Yay! Works more better with the file.
Thanks much!

I tried to run the scenario, but I got error messages on startup:

can not find file Brooklyn.sdf
can not create BOISE

can not find file Brooklyn.sdf
can not create HELENA

Do you have a design for the Brooklyn you could place in the scenario folder?

Thanks

Thank you, thank you, thank you!
Your little picture (ShipDesign.png) showed me *exactly* what I needed.
That tiny file folder has a tooltip "Open existing design". Perfect!

Yes, the Custom button does not point to my Documents folder tree (so sad).
But the Stock button lets me reach over to my ...

Thanks for trying to help! But, I don't know what you are saying.

I am using RTW3 1.01.34 with the DLC. On the title screen, there is a
box on the right that says "Ship Designer". I press it, and it launches
the DLC Ship Designer window. On the bottom right, there is a box with
a blue arrow that ...

Using beta 1.01.34 with DLC in Win11. I can save a .sdf ship design into "Custom Files". But, I don't see a way to read that file with the ship designer in order to make further corrections. Am I missing something?

I can reply to the status on two levels.

On a personal basis, it became clear that there was no way I could use:
CMO-MultiUpdateComp-v1.08.1674.zip from http://ftp.us.matrixgames.com/
File size: 9.50 GB (10,208,338,572 bytes),
to update my Win11 installation. Nikel tried to help, bless him.

So, I ...

Hi, Nigel.
I just went to Matrix My Page, and downloaded a scenario/loader:
CMO-MultiDLCSetup-Latest.exe
version 9.7.0.0
created: 2025 02 20
size: 15.0 MB (15,818,344 bytes)

But, I can't test it to see if it is compatible with 1674/1676, since all my DLC are installed now.

Thanks for the tip.

Based on a buggy Comprehensive updater:
CMO-MultiUpdateComp-v1.08.1674.exe
I was not able to update my recent patched version of CMO to 1676. Details are available at:
https://forums.matrixgames.com/viewtopic.php?t=412086

So, I bit the bullet and did a complete CMO uninstall thru the MS Control ...

Nigel, thanks for your help.

I can do a complete uninstall/reinstall. Does that mean I need to reinstall all my DLC, too?

As a P.S.
If the patch checks the registry for version data, then it seems that a Comprehensive patch should be able to cycle back to 1.07.1567.06

I located the link, found the 3 registry paths. I opened regedit, and exported my current registry as a backup--because you *always* want to be safe around dynamite.
For: ...\Matrix Games\Command Modern Operations]
installed REG_SZ TRUE
version REG_SZ 1.07.1567.06
For: ...\Uninstall\Command ...

As near as I can recollect from my backup files......
I did NOT apply the v1.08.1645 beta Comp update. That was because I didn't want to go thru a .jpg to .webp conversion.
So I think it was CMO-MultiUpdateComp-v1.07.1567.06.exe sometime on or after March 12, 2025.
I can do a registry look. I know ...