Old Setup is the common name given to SETUP31.EXE, SETUP31.INF, SETUP31.VER, OLDSETUP.BAT and OLDSETUP.INF and OLDSETUP.PIF present in early Chicago builds. The core files of Old Setup (SETUP31.EXE, SETUP31.VER and OLDSETUP.INF) were last modified in early June 1993 so they came from a build compiled at roughly the same time. Old Setup with OLDSETUP.INF does not work on build 58s anymore due to 185 missing files. It is possible to get build 58s installed using Old Setup with dummy files and components from Windows for Workgroups 3.1 but the result produced is only a semi-working and more primitive looking 58s.
Old Setup can be divided into 2 phases - text and GUI. The text portion of Setup copies all core Setup files to the desired directory then launches GUI Setup. GUI Setup asks for username (but not organization), components to install and swap file settings before installation begins.
Fig01: Setup prompts for username but not organization
Fig02: Optional components that can installed
Fig03: Swap file settings
Setup installs some components from Windows for Workgroups 3.1 (such as Microsoft Mail and Schedule+) that weren't included with build 58s. After the installation, W31TOCHI.EXE gets executed and I suspected that it makes changes to the system registry for Chicago since Chicago's registry is more complex than Windows 3.x's. Printer Setup and Network Setup happens after the execution of W31TOCHI.EXE which is then followed by updates to AUTOEXEC.BAT and CONFIG.SYS. OPROGMAN.EXE, the Temporary Program Manager gets executed right after that for setting up program groups just like Windows 3.x Setup. Setup then searches for application on the hard drive and launches SETUPFIX.EXE before it finishes.
Fig04: Setup finishes
Chicago installed using Old Setup does not contain DOS and it is required to have MS-DOS 7 installed before running it. The boot screen uses SYSLOGO.RLE and there is no animation. MERGEREG.EXE was set as the shell, it adds SETUP.REG to the system registry, changes the shell to CABINET.EXE and launches File Cabinet. I can't get File Cabinet to load because of missing registry entries but Program Manager does work.
Fig05: Chicago 58s installed by Old Setup with Program Manager as shell
It is worth mentioning that program groups are not converted to shortcuts automatically when Chicago was installed using Old Setup.
Chicago installed using Old Setup does not contain Tracker and Switch to Chicago which were present in KenOath's build 40. KenOath's build 40 is most likely fake as the GUI part of Setup is completely different. From what KenOath posted, it looks like build 58s Setup with old background. The dialogue about verifying username and organization in KenOath's build 40 is completely different to the one from Old Setup and it is exactly the same as the unused dialogue in SETUP.EXE (from build 58s). Build 40 was from early April but there is still no Tracker or Switch to Chicago in early-mid June so it is impossible for build 40 to have a 58s style Setup with Tracker and Switch to Chicago.
A mockup of early Microsoft Chicago installation procedure:
Early UI designs
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..CABINET.EXE was called File Cabinet (without >>) in the Usability Testing builds and the icon was silver. In early July, the icon suddenly became golden like in one of the concepts. It became a link with lower case "C" and silver icon in build 58s.
...Network was named World (without >>) in early July and the icon was different, similar to the one in that concept as well.
Recycle Bin was called Wastebasket back then. It changed its name multiple times throughout the development of Windows 95.The idea of having a close button at the right hand side of the title bar was already there in early July and here are some more alternatives:
The idea of storing minimized windows on the taskbar was already there in early July as well.
Here is a concept of the new File > Open dialogue:
