I've seen this topic come and go over the years and I've tended to ignore it. Mainly because I have no need for 64 bit. I suspect that it becomes an "economy of scale" issue for PGMuaic, much like the PC/MAC issue of some years ago.

At that time, there just didn't seem to be enough Mac users of BIAB for PGM to devote resources to its development. When there finally WERE enough of these PGM began their mid-year release of an upgraded Mac version.

So, PGM looks at the sales volume increases over the last several years (I'm assuming there's been increases), and compares that to the amount of resources it would take to develop a 64 bit product vs how many users WON'T upgrade if there's no 64 bit.

It all comes down to the numbers.
Of course all of this is merely conjecture, and I may be way off base. It's just the way I would look at it from a business point of view.

My 2cents CDN.
LLOYD S