Windows 10 issues with rollback and resulting issues

Recently I had the opportunity to upgrade from Windows 7 to Windows 10. Initially the new Operating System worked fine, but there were a few smaller problems as expected.

A couple of days after e installation, I suffered from what is known on the Microsoft Community Forums as the "Fatal Start Menu Bug". This also cased several Windows 10 apps to not work either or really slow while everything else was still fast. Several buttons on the taskbar were also affected and just as useless. Search did not respond either. Rebooting or the solutions provided on the forums did not help at all. The problem has been already existing in January 2015 on the technical preview.

Fortunately I had the habit of letting everything that I install to dump shortcuts on the desktop and then send them into a folder to avoid clutter on the desktop. At least I had access to most installed applications this way.

Restoring back to Windows 7 sort of worked. I was asked to activate Windows again and one or two smaller issues were not quite as I left them. There were also some file system errors and the Windows 10 file system check only takes 4 minutes.

About two days after returning to Windows 7, I booted up the machine just to find network and Bluetooth not working at all. The network status just showed "Identifying..." even after disable and enable. The troubleshooter was useless, Windows updates was not an option. Ethernet and Wifi did not work at all.

Windows Repair was attempted multiple times and when that failed, I tried to install Windows 7 in order to overwrite the files to patch up what the file system issues might have destroyed. The installer refused to install, so I decided to wipe all partitions on the first drive and start from scratch, just to find that the installer could not install to a fresh primary partition. I am suspecting that this is because the second drive of four is also bootable. This means the installer is rather stupid and the same installer is used for Windows 10.

Since I needed Internet, I installed Ubuntu Linux which had Internet already on the Live DVD before even installing. The other idea was to at least try and sort out the partition table this way. A day later, I tried again to install Window 7 with the same problem. After that I installed Linux Mint which worked fine as well.

Two days ago, I got hold of a Windows 10 ISO to try and get past the Windows 7 installation problem. Since I have an original Windows 7 DVD set, I was expecting to use my Windows 7 code since I did qualify originally to do the original upgrade in the first place.

The Windows 10 ISO never even got me as far as the partition list due to some super generic error message about some media drivers that are required, but no information about what. For Windows 7 I had to install motherboard, Ethernet and USB 3 drivers afterwards. A friend of mine with a new motherboard had the issue that his drive chipset is not supported and he could not upgrade to Windows 10. The Windows 10 installer could not even tell me what the real issue is.

My theory about the Windows 10 release is as follows:
The Operating System was released in August to the public to have enough users for the Christmas sales to keep business partners and shareholders happy. The product at the time of writing this is still very unpolished and buggy.

Update:
It turned out that the Windows 7 installation to install to the HDD required unplugging various USB devices. Why this caused such problems makes no sense. Windows 10 still did not want to install from the DVD and the message about some media thing was rather cryptic. Why I could then install Windows 10 from the upgrade provided on the desktop is a mystery to me.