Windows 1.xx

Windows 1.xx is a pre-release build of Windows 1.0 shipped by Compudata (later renamed to Tulip Computers) in early fall of 1985 with their first iteration of the Tulip System PC Compact, and is thus also one of the earliest OEM release of Windows 1.0. It was eventually found by ultrawindows and released on BetaArchive on 2019-03-02.

Overview
The base of this build was compiled on or around 1985-09-03, Compudata added additional keyboard layouts on or around 1985-09-23, and later updated  (setup version 1.xx is probably from 1985-09-25, while version 1.xy is probably from 1985-09-30). It is unclear if setup version 1.xx was also released before it was updated to 1.xy soon after, but since the Windows Upgrade Kit to version TC 1.00 (from 1986-02) explicitly mentions "Windows SETUP, version 1.xx (or 1.xy)", it can be assumed it was.

The included applications are from late 1985-08 and early 1985-09, and are already branded as "version 1.01" in the About box, though the floppy disk labels reads "APPLICATION version 1.xx". The origin of the "1.xx" (and "1.xy") designation is still unclear, the original user guide by Compudata never mentioned this designation at all. The Windows Upgrade Kit to version TC 1.00 says the following:

This document describes the way to upgrade your Microsoft Windows version 1.xx program diskettes, supplied with your Tulip pc compact or Tulip pc extend microcomputer.

Although this build contains a  file on the first disk and setup will ask for the Write disk at the end, Compudata apparently didn't include it with this build; instead, Windows Write was added as part of the upgrade to version TC 1.00, which creates an entirely new Write disk.

Different floppy sets
The original disk set from 1985-09 that was uploaded to BetaArchive was branded with the Compudata logo and came with a comprehensive user guide featuring a lot of screenshots of an earlier build, most likely from around 1985-06. A later set from 1986-01, with identical part numbers, was branded with the Tulip Computer logo instead and came with an updated user guide as well.

Media articles
In the Dutch media, Compudata talked not a lot about their first 100% IBM-compatible systems, delivered with this version of Windows, but there were some articles about the Tulip System PC Compact and Advance.

In the newspaper "Trouw" from 1985-05-08 about "Compudata moved completely to the IBM-market", they talked about the reasons and presented the two new personal computers for it

"F. Hetzenauer [..] presented two new personal computers, the Tulip Advance and the Tulip Compact. These are not only faster but also cheaper than existing computers that can be connected to IBM equipment"

- Translated quote from F. Hetzenauer

In the newspaper "NRC Handelsblad" from 1985-07-23, about "Compudata: company news", they talked about the production plans for the two new personal computers

"[..] Compudata, the Tulip System PC Advance and Tulip System PC Compact will go in production in 1985-07 or - at least - in 1985-08 [..]"

- Translated quote from Compudata: company news

The Personal Computer Magazine reviewed/tested different machines, like the Commodore 128, Schneider CPC-664 and Tulip PC Advance in their issue 9 (1985-09) from that year

In the newspaper "NRC Handelsblad" from 1986-01-13, about "Compudata: the profit doubled again", they talked about the introduction and delivery of the two new personal computers from last year

"The introduction of the two new personal computers, the Compact and the Extend (also known as the Advance), started with the delivery in late 1985-08 [..]"

- Translated quote from F. Hetzenauer

In the newspaper "Het Parool" from 1986-01-31 about the "success and the growth plans of Tulip Computers" (they changed the company name from Compudata to Tulip Computers due export-purposes) they talked and referred to this version as a "disappointed success story" (from last year).

"In addition to the old Tulip I, the company supplies the Tulip Compact, and later this year the Advance, an industrial design computer that is almost ready in the factory, but still waiting for a reliable operating system"

- Translated quote from F. Hetzenauer