This tool allows you to build custom tracks using datasets in your history for the UCSC genome browser. You can view these custom tracks on the UCSC genome browser by clicking on display at UCSC main/test link in the history panel of the output dataset.
Please note that this tool requires all input datasets(tracks) to have the same genome build. The tool throws an error when this requirement is not met. You may then have to choose a valid dataset or remove invalid tracks.