I've made a similar function here at the office.
It reads layers, dimstyle and textstyles from an XML-file.
I found XML files a bit more versatile than comma delimited files.
Whenever I create a new drawing, start working on a very old drawing or work on a drawing from outside our office, I start the function.
Some old layernames are renamed/merged to new layernames. And our standard dimstyle and textstyles are set up. (And also some other drawing parameters)
The bit that makes the layers works like this:
I read the layer specifics (name, color, linetype and some others) from the XML file, and then check if this layer already exists in the layertable.
If not, I create the layer. If it does exist, I set the color and linetype from the XML file just to be sure it ends up the way I want it.
In the XML I also have a name for the equivalent of the new layer. So if there is already a layer in the drawing with this equivalent name, I rename it to the new name. Offcourse If somehow the new layer already exists, I just merge them.
I don't have a lot of experience with coding for AutoCAD, but I made this function almost completely with the help of the AutoCAD .NET Developer's Guide.
I won't post all my code here, but if you can be more precise as to where you got stuck it might be easier to point you in the right direction.