Hi HomerJ,
The numbered folders are all part of the newer smart repository's hierarchy. They all are necessary and contain the entities (test cases, run data, attachments, defects, etc) for the ALM project. They are set up in this way by the system to use less data and eliminate unnecessary duplicates within the system. This set up has helped the system to save space and be faster in locating files, however it has made it harder for the user to navigate and find an individually desired item as was the case in the past (and therefor it is not recommended that the users try and do so).
The older repository relied on physical data links and thus each entity was saved and evaluated on its own merit. Each project had various sets of folders underneath its parent project file folder that listed the projects entities such as test cases, attachments, scripts, etc. The newer file structure relies on more logical links being associated to one file, hence if a duplicate entity (these are system evaluated to determine duplication and we aren't provided information on the evaluation process and procedures) is entered then the system instead creates a logical link to the original entity instead of duplicating and saving the new entity. This not only allows easier, faster, and more logical location and traversing of the file system, it also allows foe more space saving as it only requires to add the logical link to the associated link list and not physically save the actual file.
I hope this helps clarify the new hierarchy folder structure of the repository?
Dan