today I tried UwAmp for the first time and figured out how to install php_7.4.33.
Download the version from here, scroll down and select "VC15 x86 Thread Safe".
Unzip the downloaded file to "C:\UwAmp\bin\php" (adapt to your installation directory!) and start UwAmp.
It will ask you for the php.ini, confirm the preselected "php.ini-development" and it's done.
Notice: for me only the Thread Safe 32-bit version worked.
Tried also with the Non Thread Safe and 64-bit version but ended up with Apache starting and stopping immediately.
Also the php_8.1.12 didn't work for me, but this is the one I need to get to work.
So I will go on with testing ...
Oh, forgot to mention: php_7.2.7 can be installed directly from within UwAmp.
EDIT 2022-11-10:
Got it working with php_8.1.12!
Download and unzip php_8 repeating the steps I described for version php_7.4.33. Then go to your "C:\UwAmp\bin\php\php-8.1.12" folder and open the file "php8apache2_4.dll" with a Hex-Editor.
Now search for "php8apache2_4.dll.jump_fcontext.make_fcontext.php_module" in the decoded text and change the last part in "php8_module".
Save, DONE!!
Now you only have to change the PHP version in UwAmp and check if Apache keeps running.
Happy developing, happy testing!