Elton,
If you follow this
link you will be able to download a software upgrade from Microsoft which will allow earlier versions of word to open the newer docx format.
Yes, there will be an accompanying gpx file to the event version of the route description (RD).
There are a lot of minor differences between the latest version (3.46) of the route description- which will be released on Friday 12th.
It is unlikely I'll be able to produce a difference log between v3.46 and v3.45 - the differences will only be noticeable when you are walking the route and will not affect any pre planning. I am sorry but with working full time I have to concentrate my efforts on those tasks which will be crucial to the entrants enjoyment. If enjoyment is the correct term for walking the 100!!
Simon.