Adam sent me a mail, saying that he noticed my gripe about Live Writer: that it's behaviour around words like colour was likely to antagonise* English people (it would say it's behavior around words like color was likely to antagonize*). Thanks to him I found a fix. Adam says that the handling of the personal dictionary in Live writer is sloppy - It seems to be fixed in the build I'm running.
* It always surprises me how few British English writers know that it is perfectly acceptable to write Antagonize. Here's what Gowers says in "Plain Words"
On the Question of whether words like Organise or Organisation should be spelt with an s or a z, authorities differ. There are some words (e.g Advertise, comprise, despise, advise, exercise and surmise) which are never spelled with a z. There are others (such as Organize) for which the spelling with z is the only American form , and is also a very common British one. This being so the British writer has the advantage over the American in that we may, if we wish, use an s all the time, for that will never be wrong, whereas a Z sometimes will be. But do not condemn those who use z in it's right place.