Michail

The purpose of your white layer was already clear to me. How about this layer arrangement?:

As a group, it would look like this:

I think it's great that you can organise levels of adjustment into groups. I would not have thought of placing a pixel level in such a transfer group. Is there a particular reason that you did that? Possibly it is only for organisational reasons.

Okay  Maybe I didn't describe it that well since english is not my native tongue. But maybe with the video and your confirmation the developers get it and canfix it. 
Thanks for your help.

Sorry I completely missed you were clicking More on the context toolbar... I am sorry.
This is by design. More on the context toolbar isn't a permanent edit - it's a quick way to temporarily tweak a brush. For permanent edits, you have to right-click the brush > Edit Brush.
You will notice that if you click More, the box just says Brush - Selection whereas if you click Edit Brush the box says Brush - Editing.

It depends on the way you change the brush attributes. For example, if you change the size in the context bar  or by clicking on the "More" button , it does not work. But if you double-click on the brush in the Brushes panel or click on the "Edit brush" button , it works. I don't think this is intentional.

Hi both,
We are aware of this and it has already been logged with our developers. 

It depends on the way you change the brush attributes. For example, if you change the size in the context bar  or by clicking on the "More" button , it does not work. But if you double-click on the brush in the Brushes panel or click on the "Edit brush" button , it works. I don't think this is intentional.

Hi Michail
Great ! 😀 It works now. Sorry to be such a newbie in Windows and Affinity. This setting is not obvious at all and I am sure I would never have found the solution without your help. Many thanks !
Michel

Currently this has stopped the issue, Michail thank you for your assistance.
 

Many here have problems with hardware acceleration. Disable it to rule it out as a cause (Settings -> Performance).

The shortcut for the command "Merge down" does not work for me (Ctrl+E). This is strange because this key assignment is displayed in the settings. The shortcuts Ctrl+Shift+E and Ctrl+Shift+Alt+E work fine.
Can anyone confirm this?

and 
Please be assured that release build 1.9.1 is not likely to be the last 1.9.x release. However our customers are absolutely desperate for some of the important fixes that it already contains. Most users do not know about the beta forums or beta builds and are struggling to use 1.9.0, so we absolutely must roll 1.9.1 out very soon without holding it up. We will check for major regressions over 1.9.0 but those would be the only reason I can suggest for not releasing 1.9.1 very soon

You must explicitly select the preset again, even if it is already displayed in the preset field.
I don't know if this is planned. Maybe it would be better if the preset field was always set to "Default".

Hey Michail,
We found this yesterday  This should be fixed pretty soon...

Thanks for the explanations Chris!
The handling is not a problem if you know how to use it. As @carl123 already noted, it could be a bit more intuitive. But it works.
I think there is some redundancy in the link panel: the black squares on the left encourage you to click on them. But they are only the destination point. The link icon on the right can be clicked, and it has the function of restoring the link. So there are two geographically far apart sensitive points that serve the link.
One should unite the two elements. For example, a link symbol in a square. The link symbol should have two states.

Do the following: Open any picture. From the menu, select File => New Stack for Astrophotography. Result: Affinity Photo (Beta) crashes.

Hi Michail,
My apologies. Should have checked first. I see what you mean. I'm logging this to be looked at. 
 

Hi Michail,
It's not the same as global layers but may help in a few cases and it's something that wasn't possible before. I'm not sure if it helps @Country Cows Designs's workflow specifically but i thought it worth a mention.

My apologies; I see what you mean. It is after the panorama has been composed. And yes, that does seem to be a different Persona that doesn't act like the others.
So File > New Astrophotography Stack is not the first time a new pseudo-Persona has been added to Photo. Thanks for pointing that out. However, at least File > New Panorama starts out by asking for the images, which feels less confusing to me than the way the Astrophotography implementation works.

This just needs adding to Windows as a default shortcut. It's already there on macOS.
I've updated the bug report and emphasised that the Help suggests it should be working as default. 

Because it's only like this in the beta, I have only one explanation: you want to exchange the labels for icons in perspective. Someone started it and then the doorbell rang 😎.
I think icons are better and more space efficient, but they could be a little bit bigger.

I think we should definitely pick one and stick with it. I'll log the inconsistency. I personally prefer labels so I don't have to remember all the different icons but I think icons would be the preferred choice by most! 

Because it's only like this in the beta, I have only one explanation: you want to exchange the labels for icons in perspective. Someone started it and then the doorbell rang 😎.
I think icons are better and more space efficient, but they could be a little bit bigger.

Sorry; I looked, and saw it the same on 1.8 and 1.9 beta, but I must have been in the wrong window and looked at 1.9 both times.