Thankfully I came across this post as I was facing the same problem with Chome having issues. However my problems stem’d from getting looping on the additional mapped domains at this time.
However the key thing seems to be the primary domain for the base wordpress installation is a new .UK domain.
The additional domains i’ve setup are .co.uk however the troubles are only in chrome, if i load the additional domains in any other browser the whole network works perfectly.
Hopefully this gets resolved quickly from Chome but I think for the time being we are going to have to change away from using our .uk for the primary domain.
