If I’m not mistaken, Eclipse 3.4 (which Designer 8.0 is based on) only shipped for 32-bit Windows. Perhaps that’s why we didn’t certify it.
Designer 8.2 is built on Eclipse 3.6, which ships for both 32- and 64-bit Windows.
I don’t know of any a priori reasons 8.0 wouldn’t run on x64, but we definitely did not certify it there.
#webMethods-BPMS#MWS-CAF-Task-Engine#webMethods