What I did paste might be related that if you have multiple "pre-determined" separators.
Usually, if JMP's Open() isn't able to handle my text files, I just immediately go with scripting route and write my own custom parser.
Edit: I think the part I should have looked at was combination of End Of Field and
EOF Other(char)
If the imported text file uses an end-of-field character other than the one specified by End of Field(), this argument specifies the character used.
-Jarmo