LSMW- Specify Files

I was trying to specify files in my LSMW object. I specified a PC Test File under Legacy Data. However when I try to specify a .conv file under the Converted data section the system is asking me to specify a logical path and logical file and is making both these fields mandatory. I can make it work by specifying a logical file and logical path but this is not in my object spec so I was wondering if there is a way not to specify a logical path and logical file. Thanks a lot for your attention.