Was this resolved? I am having strange zoom behavior with the alt- mouse wheel combination as well. Horizontal zoom at cursor, and vertical zoom in general, works sporadically. Only horizontal zoom at now time gives consistent results on my system.

It's resolved. I've just loaded the Normal project template and created 100 tracks and checked it. As for the Ctrl+Alt+mousewheel horizontal zoom, the At Cursor option seem to work fine as well (I only use At Now Time, though). 

I am still getting strange behaviour
 
My original issue has been fixed
 
However, now when I "Alt + mouse wheel scroll" the screen jumps to the LAST track - ie the Track View now jumps DOWN instead of UP (which was the previous issue)
 
It does occasionally work correctly but I can't work it out
 
"It's resolved. I've just loaded the Normal project template and created 100 tracks and checked it"
 
@ Jlien X - could you please check this again but this time put some of your 100 tracks into Track Folders as I wonder whether this is causing the issue

Boydie
I am still getting strange behaviour
 
My original issue has been fixed
 
However, now when I "Alt + mouse wheel scroll" the screen jumps to the LAST track - ie the Track View now jumps DOWN instead of UP (which was the previous issue)
 
It does occasionally work correctly but I can't work it out
 
"It's resolved. I've just loaded the Normal project template and created 100 tracks and checked it"
 
@ Jlien X - could you please check this again but this time put some of your 100 tracks into Track Folders as I wonder whether this is causing the issue

 
This time, I've created only 30 tracks (100 was too many, wasn't it? lol), and put them into two track folders (15 tracks each). When the folders are both expanded, no problem. When only the first folder is expanded, no problem either. But when only the second folder is expanded, the zoom doesn't work properly. 

Jlien X
When only the first folder is expanded, no problem either. But when only the second folder is expanded, the zoom doesn't work properly. 

Thanks for checking.  So it seems there is still some work to be done.  Ugh.  I am finding more and more bugs like this in X3.  My initial "this is way better than X2!" excitement is wearing off and I am wondering again if I need to make a move to another DAW.  Really, this is the kind of thing that some decent beta testing should pick up.