Thanks!
Reverted back with a Winclone Windows 8.1 Pro x64 backup! I'm (for now) done with these upgrade issues.
It's not the applications that are crashing, but that Windows 10 upgrade KILLED most (90%) of my applications.
Fed up to trial-and-error this! The TP worked perfectly in a VM, but the real thing is a nightmare for my setup.
Later I'll try the "remove all hardware" method (exept PCI cards) like SSD's and move my Windows SSD to bay #1-4.
Cheers
My issue is easily fixable with an update. Without Steam running I am not having any issues. My next computer will be a PC so I might as well get used to spending more time in Windows because after the cMP I don't know how I could purchase a desktop Mac again without PCIE slots and drive bays. Unless Apple creates a tower again or officially lets OS X run on any Intel PC. I'm not doing hackintosh.