I appreciate the input Mofi
I had already tried UNC paths and couldn't get them to work. I've also tried to put just the filename in the config and then copy the file around the application heirarchy to see if it picks it up. No luck.
The marketing claims of this product being portable implies this functionality should work. If they can't get it to work, they should take it out of the UE3 version of the product and make a note of it in the literature. Or, they just need to put a "auto-complete" folder within the application heirarchy so they know where to look for them and get rid of the need to put a path in (just a filename). Seems simple enough.
In my mind this is a bug in UE3 and this functionality was clearly not tested. Other configuration properties work. For example, the word list path seems to get updated as the drive letter changes (i.e. the config dialog shows a full path that gets updated).