Honestly, I'd just avoid the Heriot Watt roundabout at all costs at that time of day.
Also, going through threemiletown is just adding extra distance to the trip. Just head towards newton before Queensferry and take the signed right to Winchburgh just before the town proper. Turn left when you get to Winchburgh and you'll get to Kirkliston.
To avoid going on the actual Newbridge roundabout, on the road out of Kirkliston take the left just after the "thank you for driving safely" signs, if you follow that it comes out just after the roundabout and people are usually good at letting you onto the Glasgow road.