I'm fairly sure that the installer will give you either the 32 or 64 bit version of Realm Works; rather than it becoming a 64-bit only application.
See "There is now full support for running as a 64-bit application. If your computer supports 64-bits, the product will automatically run in 64-bit." in
http://forums.wolflair.com/showpost....46&postcount=2
As evidenced by post #3 in that thread, where it says "The 64-bit build of Realm Works no longer displays a warning when importing an image larger than 4096 x 3072 pixels. This warning only applies to 32-bit Realm Works, which still shows the warning."