Have you done the usual things? Upgrade bootloader, reset and start from scratch, reinstall with NetInstall and start clean with a sightly different (better) configuration, change x86 hardware platform etc etc. ?
Perhaps I'm missing something, but didn't Mikrotik actually confirm that it's a known bug/problem and suggest the script as a fix? If so, why are you suggesting they do other stuff to fix the problem when Mikrotik says - "Yeah, known problem."
[And even if it's fixed, to have Mikrotik suggest a work-around, rather than suggest a real fix - I'm not sure which is worse?]