Program does not correctly detect current installed version of adobe reader (atm 23.001.20064). Only 32bit version is checked, this does not apply to 64bit version.
There is no free installer for 64-bit Adobe reader available.
You can install the 32-bit release with PMPC, but Reader will itself automatically update to 64-bit and then the build-in Reader automatic update will take over.
on a side note, adobe is dismissing 32 bit version