1. Yes
2. AFAIK it's in the order they are defined in.
Example:
#include <acknex.h>
void b_startup()
{
printf("B");
}
void main()
{
printf("Main");
}
void a_startup()
{
printf("A");
}
This sample should show message boxes in the order "Main", "B", "A"
For detailed documentation:
http://www.conitec.net/beta/askript-befehl.htm