My studio machine is a ACER AMD 64x2 Dual Core 4200+ 2.21 GHz 1.5 GRam XP Media SP3. I would have swore this is a 32 bit machine, but given the spec it looks like maybe it is 64bit. Anyway, I just downloaded on my work laptop which is a Dell Thinkpad, and no warning message in that environment. So it looks specific to my ACER.