The MACREX installation does the following
Creates the program folder and copies the files to it (you can select this folder if you want)
Creates the MACREX default folder and copies some default files to it.
Creates two shortcuts, one on the desktop and one under Start->All Programs->MACREX Version 8.
Adds the MACREX Program folder to the PATH
Creates and environment variable called MACREX9 and sets it to point to the MACREX default directory
Creates an association between the .mx9 file extension and the MX9.EXE program, so that indexes can be opened directly from Windows Explorer
Creates an association between .mbk files and the MX9.EXE program, so that backup files can be opened directly from Windows explorer.
Uninstalling will remove all of the above changes, but not any new files that you have made using MACREX.
It does not
Add anything to the startup files
Delete any previous versions of MACREX
Delete any indexes or already on the disk
Overwrite previous MACREX default files