The Last Guy

To get this you need to finish with a high enough score for each stage (estimate of minimum scores to obtain ??? listed below). You get 1000 points if you rescue all 4 VIPs, one point per person rescued and one point per person in the longest line.

Example one: if you have a single line of 500 marched into the escape zone, then another few here and there totaling 999 rescued with no VIPs, you get 1499 points (999 for people rescued + 500 for the longest line)

Example two: if you march in a single line of 1000 (including four VIP's), you get 3000 points (1000 for VIP + 1000 for people rescued + 1000 for the longest line).

To unlock stages
Obtain ?? (or more) on stages 1-1 thru 1-4 to unlock stage 1-X, ?? (or more) on stages 2-1 thru 2-4 to unlock stage 2-X, etc.
Complete stage 1-4 to unlock B-1.
Obtain Ladies' Man trophy to unlock stage B-2.
Complete stage 4-2 to unlock B-3.

Here are some rough estimates of minimum scores to obtain ??? on each stage:

1-1: 3000
1-2: 5000
1-3: 4000
1-4: 3000
1-X: 6000

2-1: 2600
2-2: 3000
2-3: 4000
2-4: 4000
2-X: 13000

3-1: 5000
3-2: 5000
3-3: 4000
3-4: 4000
3-X: 1050 (good luck)

4-1: 6000
4-2: 4000
4-3: 7000
4-X: 10000

B-1: 3500
B-2: 3000
B-3: 7000