h_d

I just used the replace colour function in the BETA version - I love it. It literally made my day and saved me loads of time.

The closest thing I can see is to draw an empty image frame, click the Properties button in the Contextual Toolbar, and choose scaling and Anchor options:

Click Done, give the frame a stroke if required and save it as an asset.
You can now drag the asset onto the page, Place an image inside, and the scaling and positioning of the image will match the settings you gave the original frame.
Not sure if it's a complete solution, hope it helps.
H

A slight variation...
Rasterise if necessary as @Alfred says. I then used a fairly strong Levels adjustment, dragging Black right and White left to even out any colour variations in the red:

Then click on the red area with the Flood Select tool. (When I initially tried on uploaded image, I was getting a lot of half-selected pixels - hence the step above. It may depend on the Tolerance settings for the Flood Select tool.)
From the Select menu choose Outline. Set the Alignment to Inside and adjust the Radius as required:

Click Apply, go to Select and choose Invert Pixel Selection.
Press the Delete key.

Deselect.
Cheers,
H

Hard to describe in words, but group the red lines and drag them over the orange shape as shown below:
 

Screen Recording 2020-10-18 at 00.56.28.mov Check on the highlight in the layer panel. It's not intuitive or straightforward but the highlighting from just away from the left-hand edge all the way to the right-hand edge of the orange layer means you're doing it right.
 

WOW!!  Fantastic!  Thanks for the video, that made it so simple and easy!!    You saved the day!!  Thanks so much!  You Rock!!

We shall overcome...

I have set my Preferences back to match yours exactly.   Hit Close, and Restart.   Then closed Photo down and opened it again.  Placed an image, rasterized it, and tried to use the plugin.   Same story.   It just shows the blank Watercolor Studio screen.   I think we should give this a pass for tonight.   You have been so wonderful, but enough is enough for one day.   I have sent the Tech Support people at Watercolor Studio an email, and suppose that in a few days they may respond.
You are a Gentleman +++++++++++++++++ and I do appreciate everything so much!!

That is bloody gruesome.

@h_d  I will give it a try.  @firstdefence The "look" has its points, but being female, I am not quite sure how I can wangle the beard.  Although in this day and age, who knows?

That is bloody gruesome.

Thanks for your input!

I think those iOS 12 assets were a sort of giveaway with Designer many months ago. They have never been updated and don't appear in any other apps. 

I am an expert at that one 😂

Hi @h_d, did you save the defaults after synchronising them?

Hi @h_d, Murfee is correct, Synchronize Defaults will only affect the current document, unless you use the Save option in Edit > Defaults.

To run the .php script in MacOS:
Download the .zip file from @Lagarto's post above. To your Downloads folder. It should unzip automatically, giving you a file called createasepalette.php.
Launch Terminal.
Type cd Downloads and press Return.
Type php createasepalette.php and press Return.
The .ase file (test.ase) will be written to your Downloads folder.
Quit Terminal.
In Affinity Photo (or any Affinity app), click the Hamburger icon in the Swatches Palette and chose one of the options from Import (Document, Application or System). Navigate to your Downloads folder and choose test.ase.
Result:

Cheers,
H
 

Perfect, it works! I was able to format the text and the table of contents as required by the university, and the work is saved. Thanks to your template and the explanations for the settings in the textstyles, I understood how to do it. Thank you, thank you, thank you!

Nope, sorry, didn't help. 

If you mean the "cell margins" within a table, then reveal Cell in the Table panel (View-Studio-Table if it's not showing) and adjust the insets there:

Further refinement to the excellent work by h_d
Coloured Names.afpub
Instructions included.
We seem to have not answered your question about Designer. Sorry about that. But if you have publisher this will help a lot more.
To get this to work in Designer is far more difficult.

I initially thought of Symbols in Designer, but I can't see any way of keeping even spacing between different name lengths, or preventing issues with overflow with long names.
So here's my take based on @Old Bruce's ingenious solution in Publisher. It requires a pretty complex layout, but I think it works. Sorry it's not in Designer...
You have to account for very short names (eg 'Jo') and very long names ('Montmorency de Coverley' may be over the top, but you never know...)
In Publisher, I have a row of single-line text frames containing the repeated Author field with repeating global colours. The left-hand sides of the frames are offset  (off the document margin) to give the diagonal striping. They're aligned at the right. The text itself is aligned left in the frames. All the frames are set to Hide Overflow in the Text Frame panel.
To get a full spread of names, I set the Author's name to 'Jo' and fill out to the right-hand end of each frame:

Once you've set this up, which takes quite a while, then you just have to change the Author field once (™ Old Bruce). It may look odd having the lower frames stuck out so far to the left, but it's actually necessary when you get a really long name:

(This is where hiding the overflow comes in handy.)
As pointed out, changing colours can be achieved using Global Colours in a Document Palette in the Swatches panel.

And if you switch to Preview Mode you get a clearer view of the final result:

.afpub document attached for clarity.
Cheers,
H
 
namespace.afpub

Here is a short video demonstrating in Publisher using Character Styles for the instances of Author fields to give the colour to alternate names.
Screen Recording 2020-10-14 at 8.34.44 AM.mov .  

Using guides...
With the Node tool selected, in the context toolbar, select Align to nodes of selected curves (the left-hand button next to Snap):

Ensure snapping is on.
Select the node with the Node tool
Drag a vertical guide from the left margin to snap to the node.
Drag a horizontal guide from the top margin to snap to the node
Snap the circle to the guides.

Screen Recording 2020-09-17 at 14.11.53.mov Hope it helps!
 
 
 

Assuming this is in Designer, I think Layer-Expand Stroke should do what you want. This basically creates an outlined shape from the selected curve. You should be aware that it's a destructive operation - the source curve is not automatically retained - so you may want to duplicate your original Curve layers before applying it.
Before & after:

You can do this after converting the circles to curves, then use the node transform mode.
 
2020-10-12_16-53-54.mp4