Smoke sim completely different in Blender 2.63a vs 2.64a (same file)

[loogas]

I’m doing something with a deadline and I’ve just had a nasty surprise from Blender. Have there been any changes in the way Blender simulates smoke between versions 2.63a and 2.64a?
I’ve simulated the basis of my smoke in 2.63a yesterday but then I needed to fracture stuff so I opened the same file in 2.64a and continued my work there. I left the sim with higher settings for the night and it is completely different. I went back to simple settings, opened the same file in 2.63a and 2.64a to compare the smoke sim results and to my horror they are completely different!

I’ve attached two screenshots:
Blender 2.63a

Blender 2.64a:

The particles landed in a different spot (I don’t know why but that’s not the case here) but you can clearly see that the smoke is a lot less dense in 2.64a. Why? Please, tell me why?

I generally noticed that working with smoke simulations in Blender 2.64a is a bit more difficult - it is less visible in the viewport when I increase divisions. At some point I just have to render because in the viewport I can see nothing. In older versions it was a bit more intuitive.

Thanks for any help

Update:
It seems it’s true - the way the smoke is simulated has changed. I’ve used another test file and here’s what I got (same file, same frame):
Blender 2.63a and Blender 2.64a respectively:

[kennfletch]

Like your setting for your explosion mind posting?

[loogas]

Sorry for the delay. The settings in the examples at the bottom (I thing you’re talking about those) are the same but just look different in two different versions of Blender. I did the test fast to check Blender so there’s no special stuff on my part, everything was taken from Andrew Price’s tutorial on explosions, just follow his steps Here’s the link.

Have fun

UPDATE:
Well, it’s done. Here’s a link to the music video. The Blender explosion part starts after 4m 40sec mark:

I hope you’ll like it