Hi William,
It appears that there is a formatting error with the .txt.file you selected there, could you perhaps navigate to the file, open it in a plain text editor and send us a screenshot?
Alternatively you might try loading the data in from the EnrichmentMap menu from within CytoScape directly rather than using the connection from the GSEA application which can encounter occasional bugs as if EnrichmentMap has made API changes on their end.
-Anthony
Anthony S. Castanza, PhD
Curator, Molecular Signatures Database
Mesirov Lab, Department of Medicine
University of California, San Diego