This question is asked out of total ignorance and no access to a 64 bit windows machine, but I would like to know whether there is anything special that needs to be taken into account regarding a 64-bit registry and whether there is a regedit64 the way there was a regedit32.
Yes, there is a distinction between 64bit and 32bit regedit. There are both 32bit and 64bit keys in the registry. The default 64bit registry editor will show both of these, the 32bit one only the 32bit keys.
See this MS KB article for more details.