ServicesCtl is licensed under the GPL. Please read the licence. A good source for the understanding of this license can be found at Wikipedia. The important points are (in my opinion and without legal advice):
- You may use this program without restrictions, either as private individual or commercial.
- You may modify the program to satisfy your needs. If you publish the modified program, you must publish the changed source code, too. If you don't publish the modified program (internal usage), you don't need to publish the modified source code.