2 weeks is not really enough time to make a difference, so aaron's advice is spot on. But here's how I would approach it...
2 weeks -- 1 week
Do two 80-100k efforts this week. 40k of these rides should be "ITT race simulation". Make sure the course emulates the ITT course in terms of elevation profile. The rest of the week: concentrate on using a slightly larger gear than you'd normally use.
1 week -- ITT
Do one 80-100k effort (same as above) with 7 or 6 days to go. Your legs will be tired from the past week's efforts and using slightly larger gears. So as you approach race day, decrease the distance you're riding each day down to about a 45-minute ride 1 day before. However, and this is really important, throughout this week, make sure you're maintaining the intensity, but just cutting the duration.
On the last ride prior to the ITT, keep the intensity, but concentrate on spinning a quick cadence. Do 1 or 2 surges where you drop it into a big gear, and simulate the ITT effort.
Days completely off the bike are counter-productive and don't really help. (Only 1 day off the bike per week.) If you need a restful ride, just take an easy, 1-hour spin.
If you have them use rollers to get your position down and spend a bit of time - 15-30 min in your TT position. This will be difficult, but will give you more rapid feedback as you try to improve your form. Form / aero-ness matters a whole bunch on a 40KTT.
Of course shave you legs - and arms if you don't go long sleeved...
My recommendation, since you haven't done one before is to stand up 3 times during the TT. Once at the 1/4 point, once at the turnaround, once at the 3/4 point.
Just to get out of the position.
I agree that standing/stretching out a couple times during the event is good, but I would choose to do those at points on the course where it isn't so bad instead of a fixed % of completion. A short steep hill is a far better place to stand than a very fast slightly downhill portion.
There isn't much you can do for training. I would try to spend extra time in position and do one or two sessions of VO2max intervals but that's just me.