Windows 10 is not released yet for a very good reason. It is still in BETA.
Thus any "experience" from the technical build is useless.
Tech build has hardware compatibility issues to solve.
Tech build has more issues to fix.
Tech build is so people will use it and send feedback on microsoft, so the final release will be as bug-free as possible.
"
I'm quite afraid that the VX ACE games won't work at all with windows 10".
Same fear came for Windows 7 and 8.
Still VX Ace runs on both.
And you r fear is based on trying a VX Ace game on a DEMO of an Operating System that is NOT YET compatible with all hardware whatsoever.
So... let's be a little patient and fear free, shall we?
PS: If that's the case, then many other programs wont work too. Thus there will be a compatibility layer or solution for this (worst case scenario).
I hope so, and this is an MS issue really.
Didn't heard Satya Nandella saying that it won't be back compatible (nobody would buy that in that case anyway that's why I assume everything will be ok)