I have also had major priblems getting sync to work, and I wouldn't bother with HTC because, as far as they are concerned they have not released the phone to the market yet and so were unwilling to help.
When I spoke to orange they stated the the software is from HTC so they are responsible for it and would not help.
However after a bit of ferreting around on the phone I came across this online set up guide and have pulled out the following link
Learn More
on there is a download section which has the latest HTC sync and I found that this has been pretty good so far, with the exception of updating my outlook calendar from the phone.
Hope this is of help