So the Harrow title says that if the ship does a speed one maneuver in the Determine Course step you get an extra yaw for the rest of the activation. So does that mean if I have engine techs I can do two speed one movements with two clicks of yaw, since the title's bonus doesn't expire until after the activation and engine techs activates before then?

Yes. Although it won't be quite the same as the normal double-double-click drift as you have to swap sides with the tool.

The Harrow bonus never really expires. It applies during the "Determine Course" step "When you execute a speed-1 maneuver." Engine Techs lets you "execute a speed-1 maneuver." So the Harrow bonus will work during the Engine Techs move. It applies whenever you do a speed-1 maneuver.

Which is slightly different to Moff Jerjerrod; which gives you an extra two clicks on your speed chart until the end of the activation - but only on the first joint of your current speed (so only works with Engine Techs if you are at speed 1).

And is completely different to a normal Navigate Command extra-click, which expires at the end of the first maneuver so doesn't work at all with Engine Techs.