When using 4D, temporary files are stored in a location external to the database and application folder so that there will not be permissions issues with reading and writting.

On Windows the locations are:
C:\Users\{UserName}\AppData\Local\
C:\Users\{UserName}\AppData\Roaming\


On Mac the location is:
HD:Users:{Username}:Library:Application Support:
HD:Users:{Username}:Library:Caches:

The location will contain a 4D folder for databases opened with the 4D app and a 4D Server folder for databases opened with 4D Server.

For built applications, instead of the folder being named "4D" or "4D Server", the folder will have the name of the Application instead.
For example:
C:\Users\{UserName}\AppData\Local\{AppName}\...