Just had a brief play with CDTSX4.  Like some of the new tools - the halo should be really useful.  Also, I'm glad to see I can now use the standard align shortcuts (L,R,C,T,B,E) that are in Draw (these were not customisable in CDTS12 as their function was locked to a tool modifier).

I was momentarily pleased when I saw a seaparate control for snap to guidelines.  In CDTS12, there was no separate control for this, so one had to switch gravity snapping on or off (and there was no separate guideline option in snapping control so I assume the snapping was treating guidelines as objects).  However, even though there is now an option to turn snap to guidelines on or off in CDTSX4, it does not work!  The only way snapping to guidelines seems to work is that they are functioning as an object (i.e. gravity snapping has to be on as it does in 12).  It would be really nice if this was fixed for the official release.
cheers
Bill