Mass is on a log scale. The 0-100% range maps on to 0.1 to 10 times the mass of the sun (50% = 1 solar mass).
Eccentricity for the planetesimals is from 0 (circular) to 100% (parabolic), via flavours of elliptical.
This page contains JavaScript that emulates an early simulation of planetary system accretion (Computer Simulation of the Formation of Planetary Systems, Stephen H. Dole, Icarus, 13 494-509 (1970)), along with a few tweaks of mine to allow for different stellar masses, and to generate planetary parameters based on the rules of thumb from his RAND report, Habitable Planets for Man.
The acrete script used, along with slider control script used and this page, can be run offline (save as “Web page, Complete” if you prefer).