Hello everyone,
I would like to save my own level under MacOS Catalina ( 10.15.6 ), but I always get this error message!

Thank you, does anyone have an answer for me!
PS.: I am not a "terminal" guy. thx ;-)

The level editor will automatically save the level in the folder path where app is located on your hard drive.

You need to make sure that you have write permissions to that folder. 

I'm not a Mac guy myself, but I believe you can find some info on how to do it here for example: https://support.apple.com/guide/mac-help/change-permissions-for-files-folders-or-disks-mchlp1203/mac

(If you are unable to set the write permissions for the particular folder where it's currently located, perhaps you can move the entire app to another folder on your hard drive). 

Hope that helps!

Many thanks for the friendly answer! 
I tried both suggestions before ... and unfortunately I got the same "error message".

But thanks again for the help.
With best regards from Vienna!

PS: If anyone can think of an answer ... 
I don't use "FileFault", no external partition, nothing fancy -
all a simple 08/15 MacOS installation.
Thx!