How very odd, I installed Arachne again today and now it actually looks more like 1.64 (although several files on the other install say it's 1.64 it looks like 1.62). Anyway, scratch most of the things I wrote in other mails about 1.64, they don't seem to be true. Now why I got this weird result after installing I don't know - everything except core.exe seems to be from 1.64. Core.exe looks like a version I've compiled myself (although without any changes) - but all those have been located on F: and I installed to c:\arachne3 (which didn't exist before - dir will confirm that) - and above all I couldn't have copied one to that directory after installing Arachne there and before testing it.
