The reason the value of the string was -1 was because there was a localized description entered in that same area, in the text box. The -1 allows you to use the local description rather than going through the description provided by the .tlk.
That you are learning to get around is an accomplishment
I am just saying that yes, it will be a problem throughout your playthrough, and you will have to do these steps repeatedly, and some may be more difficult to work out.
You seem to be taking this as an opportunity to learn how to mod. If that is the case, you have given yourself a challenging assignment that can teach you a great deal!