What's the most computation intensive part of create program?

[lin-ycv]

i'm curious as to what makes a few hundred targets take 5 seconds to calculate

I've done programs that have a lot more targets, and it only takes 2 or so seconds.

Does a detailed robot/tool mesh model causes increase in time? or does long distance movements increase time?
What tips are there to minmize the computational time.

[visose]

Linear motions will take longer than Joint motions. Longer distance traveled in linear motions will also take longer, irrespective of the number of targets. Some robots use a numerical IK solver, which takes longer than the analytical ones, but this is not the case for KUKA which I think you are using.
You can reduce the time it takes to calculate by increasing the Step size input (S). You can keep it a higher value while making changes and lower it back to 1 mm at the very end before exporting the program.