I'm not fondle of win8, i hate it and usually does no support abot those issues.
I'm using a method on my coworkers win8 insytall to allow them use old and incompatible software (not everything run but more than half).
This is a dangerous method, do it at your own risk; if you aren't prepared to loose the installation with all settings do a full backup, anyway that never happened in my case.
With securety boot disabled you need to start another operating system, or a windows pe on the same machine that has the securety management tools in cluded; in alternative detach the hdd and connect it temporarily to another machine, an usb adapter is fine like connecting it to the internal sata.
Select the letter of the offline operating system (doesn't enter the drive) , and under the securety tab:
Add the user "everyone".
Make "everyone" propietary of the entire hard disk including all files.
Give full access to the entire disk for all users.
Repeat the steps until you have no more errors.
Now your program can happily read/write everywhere, you can install the programs everywhere, but you can easily delete critical system files killing windows or get old viruses infect your system.
That's a double edge sword, but remember that we survived more than 14 years with this settings on the previous versions of windows.
