On the Dashboard screen of scorm-NEXT, in the Server section, the amount of contracted space and the amount of remaining space are reported.
You may notice that the content you have uploaded to the repository takes up more space in scorm-NEXT than the original SCORM packages. The reason for this is because the original SCORM packages are compressed in a ZIP archive, whereas in scorm-NEXT those contents are extracted from the ZIP archive and stored uncompressed.
You can compare the disk space used by scorm-NEXT with the space occupied by SCORM packages by decompressing these packages and calculating the size of their uncompressed contents.