iCloud - migration – two days and counting

It’s only a matter of minutes to transfer to iCloud! It’s so easy.
Or is it? I migrated all yesterday.
I have three Macs (27" iMac, 15" MacBook Pro, 13" MacBook Air), an iPad2 and iPhone 4S.
I’ve been on to AppleCare for over 4 hours yesterday and a couple today, gone from level one to level two (a very helpful Polish gentleman from Cork, Ireland) and has now been upgraded to level three: given a temporary password so that they can monitor progress and behaviour.
Firstly, iCal worked fine with everything entered on every machine (except the iPad) uploading to iCloud and then to each other machine within seconds/minutes.
Secondly, AddressBook data entered on iPhone and iPad uploaded instantly to iCloud and thence to the other, but not to any of the three computers.
Nothing entered on any computer uploaded at all.
After 4 hours round and deeper into the iMac system, we packed up at 7.30pm, very tired and hungry.
Today around 2.30 - 3 we started again.
This time, we first experimented by creating an admin account then copying the Archived Addressbook onto Address book. Didn’t upload either.
Next, back on normal identity,  exited iCloud, deleting the data so that both Address book and iCal on computer blank. Then logged back into iCloud and both Address Book and iCal downloaded.
Next, created new iCal item on the computer calendar – uploaded immediately.
Next, created new Address Book item on computer address book. Took up to 15 mins to upload – though it did now upload eventually. Having uploaded it then spread very quickly to other devices.

So awaiting the monitoring to see why the uploading of Address book data takes so long (and slows computer down ridiculously).

Then we have to discover why the iPad won’t upload data on iCal and why all computers takes so long to upload data from Address books.
THe original situation of no communication between the 3 computers and iCloud either way has gone but its cause remains a mystery (to me at least).