Disk Director 12 install crashes Windows 7

The essence of this topic is to identify why an apparently successful install of DD12 crashed windows. there is some background with DD12, summarised, and then way this particular issue played out

Background.
In mid July I had a motherboard failure on a desktop PC. After recovering the hardware with a new motherboard having a dual UEFI BIOSand OS, I re-installed licensed copies of TIH 2012 and DD11. Those apps installed and ran under windows OK, but neither of them created recovery disks which would boot on the new system. They would however work on an older legacy BIOS. The story of that exercise is in case 94536 on the old true image forum. Shadowsports replicated the fault, indicating that the older Acronis applications could not handle the UEFI BIOS. and recommended an upgrade, which I did. The bootable recovery disk for that works.
Following the same advice, I upgraded from DD11 to DD12 on the same machine. That was a disaster: DD11 would not uninstall, DD12 would not install over it, consistently failing in the same place. A catch 22 situation. And the fixing thereof under case 02507068 went thru the contact centre support, where everything an agent tried failed but in the process every Acronis application on the machine was either removed or made in-operable, the expert engineer group (same result, lots of logs) and finally to the development group in Russia before it was fixed, not 3 days ago. A fortnight of heartache because it looked like DD11/12 had compromised the registry, and I would need to do a complete system rebuild as a result. This is the email header for that support activity:
[02507068] Disk Director 12 will not install [ ref:_00D30Zcb._50050fuTmF:ref ] which I was continually advised not to change.

The current problem.
The objective was to install DD12 on a legacy BIOS laptop, removing the prior DD11 install first. That machine has TIH 2012 latest build installed. Uninstalling DD11 via control panel seemed to go as expected. I ran Cclean to remove old files and get the registry right, and re-booted. Boot OK. Check: the F:\drive which the DD11 app was installed to existed but basically empty (2 items left).
Ran the DD12 self-extracting file to install, and that seemed to run OK. Entered the license keys, and continued. Got a message box saying the installer had a problem with 2 files which were running - both scheduler services. A choice was offered: close them separately (how would one do that?) or to continue and the installer would close them and re-start later. Selected continue. Got a completion message and a re-start notice, which I did (click restart).

The re-start boot failed outright, at the DOS-like text screen just after the BIOS notice: problem with newly installed software, one boot device not found, options for continue to boot or do a repair. The repair option was essentially un-doable because windows was pre-installed and I have no distribution disk to work from. Choosing both those option did not change things. Boot windows normally also failed. A cold re-start was no better.

So now I have an apparently successful install of DD12 that has crashed the machine seriously.

The only way out of this was a C drive restore, using the TIH2012 bootable recovery disk created for the machine and a 2 week-old backup file. That worked. And when it was over and windows booted again, the DD11 icon was corrupted (because the files it referred to were now missing) and the programs and features still showed DD11 installed. reasonable result, given what had happened.

Rather than repeat the prior disaster with DD12, I simply re-installed DD11 to the same places it was previously: specifically the when the installer gave options to modify, repair etc, I chose repair and the app was re-installed as before. And it works on windows test.

So, now I am very leary about the quality of the DD12 application, but it still provides the functions especially bootable recovery I need and no other app that I know of does.

The question
1. Why did the DD12 installation crash windows?
2. Is there a way to install DD12 successfully without these re-curring disasters?

Davidk