Sorry to hear that problem with uTool.
Some people reported this issue. We planning to release the new version of uTool by end of this month, with the new version that problem must be solved.
Until this release please use the “directory” option on your export tab, and export the content to your local HDD. When the exporting done, please copy the “Recording” and “Music” folder to your USB HDD root folder.
Sorry for the inconveniences.