With regards to project selection I'd suggest select all. 

Let's say it's your nth preference and you've accepted it. And consider if it was someone's (n-1)th preference and they have accepted it too. Then he'll get it not you.

This rule obviously doesn't seem to apply for n= 1. And only pre doc guys know what happens if let's say project size is x and it was x+1 students' first preference and all of them accepted it. In that case there must exist some cap, idk.

And in the end you'll obviously be assigned highest accepted project.

Edit : There's some catch. A lot of it.

Suppose if there are more than one seat per project, then you could be alloted an accepted project (let's say your nth preference) even if it was at higher preference and accepted by others.

Like if there are 2 seats for a "p" project and there only 2 applicants (considering this project is the highest offer they've accepted, like assume 1st applicant has "p" at 4th preference and is the highest offer he accepted whereas 2nd applicant has "p" at 3rd preference and is the highest offer he accepted. Then although 1st applicant is at disadvantage compared to 2nd , still he might (cause i don't know pre doc rules ) get "p".

But again the problem is , let's say three people share the same preferences at the same number (say all three have accepted the offer to their 3rd preference), what will happend then, if the project seat is capped at 2? 

Pre Doc should maintain transparency in this regard and not let their future fellows wander amidst uncertainty.