The first time you start, it doesn’t automatically find the COM port. I just started typing in different COM#s until I got the right one. If you have more than one battery I recommend that you first hook them up one at a time and use the “find battery” button. It will tell what your battery number is. You can then change it to whatever number you want. When you have the module numbers you can chain them together and still read the information for each individual module.
Much of the information I have came from here. 300MPG