Program options values are meant for initialization of main interpreter states/values in order to prevent any unpredicted machine behaviour on software start.
Measurement unit mode. User can choose between G20 or G21.
Plane mode. User can choose between G17,G18 or G19.
Distance mode. User can choose between G90 or G91
Distance mode IJK. User can choose between G90.1 or G91.1.
Distance mode ABC. User can choose between G90.2 or G91.2.
Cycle Return Mode. User can choose between G98 or G99.
Lathe mode. User can choose between G07 or G08.
Blend mode. User can choose between G64(path blending on) or G61 (path blending off).
G-code programs include traverse(aka rapid) machine moves. During these moves, machine is not cutting the material, instead it is moving above the material usually moving to next cutting position. These moves are executed with G00 g-code command. You cannot set speed value of traverse moves with corresponding g-code command (unlike feed speed with F-word). With this parameter you can set default speed value of traverse machine moves when G00 command is executed in program.
G-code programs include traverse(aka rapid) machine moves. During these moves, machine is not cutting the material, instead it is moving above the material usually moving to next cutting position. These moves are executed with G00 g-code command. You cannot set speed value of traverse moves with corresponding g-code command (unlike feed speed with F-word). With this parameter you can set default speed value of traverse machine moves when G00 command is executed in program.
G-code programs include feed machine moves. These moves are executed with G01 g-code command. During these moves machine is cutting the material. Speed of feed moves is set with F-word g-code command. If g-code program does not include F-word g-code, then value of this parameter will be used in program.
Spindle speed is value of RPM(Rotations Per Minute) of Spindle. In g-code program, this is set by S-word g-code command. If your g-code program does not include S-word command, then value of this parameter will be taken into the account.
Transformation coefficient values.