Please explain more what " -r " does exactly. And why 3 starting points?
"-r 61" will make all points start at a random offset in 61 bit range.
The 3 sample starting points are just for information/confirmation the correct range is used.
If your BitCrack is generating 37,748,736 starting points then each point starts at a random offset in 61 bit range.
It is easy to adjust the code now. Simply adjust in generateStartingPoints() function.
You can combine -r with --keyspace if you need to additional control.
Please "git pull" to get the latest version that also contains fixes.