I understand that After Effects CS6 is only compatible with 64-bit systems. I am trying to find a 32-bit version of After Effects 5.5 that I can download from Adobe to install on a 32-bit Windows (7 Pro) system.
There is no such thing. The last 32bit version of AE was CS4 and that was now almost 5 years ago. The trial can be obtained using this method, but you can no longer buy it anywhere:
Direct Download Links for Adobe Software
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