You should not have any problems with if you follow the instructions in that first article.
The important thing is to backup the Registry first if you have to edit it. I think it explains it but in simple terms you just type in "regedit" in the Run box and at the top of the window which appears click on the File tab. That will offer you several options, the one you want to use is Export. That simply backs up the Registry to a location of choice. Name the file: Registry Backup with the date.
When you click on Save that's what it will do. It should take takes 10 -30 secs depending on your system. There's no progress bar, just the whirly gig cursor to indicate something is happening and you get no confirmation of the backup having been made when it is finished so check you have a .reg file at that location afterwards. It should be several hundred MB in size.
If something goes wrong with your later Registry editing you just reverse the process, instead of Export you use Import and that file will be used to return the Registry to its previous state.