Differences between Compatibility Troubleshooter and registry key set

Hi all,
according to this tutorial
https://www.tenforums.com/tutorials/1...dows-10-a.html
compatibility settings could be done in several ways.

However, I'm experiencing a different behaviour if I set compatibility through registry key or through Program Compatibility Troubleshooter and I need some help about it.

I have a little application, written very long ago on a XP system, that uses an API for setting sound volume on mixer.
This API was no longer used in Windows 7, but running the program in compatibility mode was enough to make it work.
I made a script to set key in registry at
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\AppCompatFlags\Layers
and all went well.

Recently I went up with W10 and did the same. Executed the script and all done.
At this point I realized that memory limits were exceeded and resolved myself to recompile that program with updated API.
I went to regedit, deleted the key and retried to check memory (expecting the mixer call won't work).
Here my first surprise: it worked! and memory usage was still high!
It was as app was launched in compatibility mode, even if nothing was setted so. No key in Layers folder and no checkbox in Properties/compatibility Tab.

I then tried to use Compatibility Troubleshooter to see what it would have suggested; clicked on reccomended settings and it suggested no compatibility, tested app and BAM!
Second surprise, it doesn't work and low memory usage. Retried to launch it manually and same.

I tried several times and always the same effect applies.
It's like deleting keys in registry isn't enough to return to previous no-compatibility settings.

Does the Compatibility Troubleshooter set something different?
Or there's some key I'm missing?
Anyone else has experienced this?

Sorry for long post. I wanted to explain from the beginning, cause I'm still confused myself.

Thx
David

Hi Dalchina,
I used to set registry key as a part of a setup script that set compatibility mode for some processes and a bunch of other stuff (the mixer process is only a part of a small suite that I distribute as gadget to some friends).
Anyway I want to avoid a user to have to manually check on compatibility checkboxes for every application I eentually develop in the future..

Anyway, I tried to reset compaatibility via the GUI but the effect is the same than removing registry key.

Troubleshooter makes something different and was wondering what it is.

I don't like very much this self-decided action from Windows, I'm worried it could hide something else.