We've just released the 1.0.5 maintenance release of uniVocity which fixes the hanging "open folder" button on the license request wizard. This was caused by a bug in the JDK (versions 6 and 7) so we removed it.
Additionally, the StringWriterProvider class in our public API had a bug that caused it to incorrectly inform whether or not contents had been written to the output. This caused issues when running the examples with batch operations disabled
Please upgrade to version 1.0.5 here.