If the “Register” key is not visible when the program first opens, do an Alt-Tab,* then another Alt-Tab,* and you should then see a pull-down menu bar across the top. Select the menu for SoftOrbits to see the Register key option. After registering the program, the pull-down SoftOrbits menu will no longer have the register key symbol.
*The Alt-Tab will switch the program to not be the front program, then the second Alt-Tab will bring it back.