Hi Ewan,
Sorry, I had tested that, but forgot to mention it.
In Office 2007, Powerpoint and Excel received pretty much the 'full treatment' upgrade to the new Office graphics engine, While Word
only got a partial nip/tuck. If I recall from the beta for the new engine the Shift = constrain feature was one that wasn't fixed
for Powerpoint/Excel, but it does still work in Word, so a workaround I've used has been to draw it in a blank Word document then
copy/paste to Powerpoint.
In Word you also use the snap to grid feature to constrain the lines to intervals. The intervals I get without the snap to grid
feature on are less than 45 degrees though.
=============
Unfortunately you missed a very important feature.
In previous Office2003 Powerpoint, pressing down the shift key would
constrain the straight lines to multiples of 45 degrees, so you could make
absolute vertical and absolute horizontal lines.
I can't believe this issue hasn't been addressed yet.--
Bob Buckland ?
MS Office System Products MVP
*Courtesy is not expensive and can pay big dividends*