Easy, quick, way is to extract the entire contents of the cab file to a folder with the same name. That way, you can edit the .xml files easily, then just save them again, all in the folder. No extracting then recompiling.
Alternatively, and you'll still have to extract the entire contents of the cab file to do this, put them all in a folder someplace, name of your choice. Then using a utility called CabPack v1.4, put everything back into a cab of the same name. IE: Once you extract the contents of the .cab file, rename it to something else. Like test_unpacked.cab vice test.cab.
Simple program to use, excellent documentation, too. Read the documentation on how to use it before you try it. Anywho, CabPack will stuff everything back into a cab file, name of your choice. So essentially, you take the contents of the cab file you unpacked earlier, and CabPack makes a brand new cab file with those contents. Like if you are using my example, you unpacked the entire contents of Test.cab to the folder Store. Then, you renamed Test.cab to Test_unpacked.cab. Then, you told CabPack to create a new cab file named Test.cab, using the contents of the folder Store. You now have a recompiled .cab file the plane will recognize, as it has the same name as the old one.
As I said, it's much quicker and easier to unpack Test.cab to the folder Test, then rename Test.cab to test_unpacked.cab. Now you can repeatedly edit any .xml file to test out new features or functions you may want to add, or subtract, without recompiling the cab file over and over. The sim will recognize the folder Test as easily as it did the file Test.cab.
Is all that as clear as mud? By the way, CabPack v1.4 is readily available freeware. A quick Google will find it easily.
Pat☺