Hi again!
The oral is normally just a FEW brief questions to make sure that you know what you're doing. E.g "When you check the oil, what level are you looking for. How would you top it up and with what type of oil". That sort of thing. Or "What is this aerial for". Nothing too hard - certainly not the "Why is this screw head circled in red" nonsense we used to get in military training!
The diversion should go something like:
"Tell me what this place is coming up ahead."
"It's the town of Anyplace"
"OK - pretend that the weather 5 miles further on is such that you can't see the ground. WHEN YOU ARE READY, I'd like you to divert to here" (Pointing out where 'here' is on the map)."
You should then have time to draw a line from Anyplace (or other nearby landmark) to 'here' - I suggest a chinagraph pencil and the edge of the checklist. Measure the distance (my checklists have a 1/2 mill scale on the edge!), write it down. Find a VOR rose, use your checklist like a parallel rule and measure the mag track. Write it down. Then apply Mental Dead Reckoning to obtain your GS and Track, then set off using a combination of accurate flying and map reading.
The emergency section will only be failed if you do something daft! As for maintaining heading, height and speed - well, the limits are quite generous and most Examiners won't just be sitting there watching for a limit to be broken....
Bear in mind that I'm talking about a JAR-FCL PPL(A) conducted in the UK - things may be different elsewhere! Have another read of Pink_aviator's post to get a feel for how it seemed to a somewhat nervous pilot!
Good luck!!
Oh - and the screw was circled in red because it had to be a special short-reach type so that it didn't foul the control cables under the skin!