>>> Will the "10 users group licenses" package allow 10 users to connect using a single user login simultaneously?

If you use a single user logon, then you don't need to order 10-user license. Multiple users can logon the same account at the same time. There is a max limit (designed to fight service abuses), the info is not released and can change from time to time.

>>> They will only be able to make changes to their own "personal" file but will be able to view everyones file.

If multiple users logon as the same DriveHQ user account, then DriveHQ system can only treat them as the same user. Therefore, you cannot apply different security settings to different folders / files.

Based on your description, you do need to create multiple sub-users. Different users need to logon as different sub-user accounts. Please note users always have full access to files in their own accounts. To limit the access the level, you need to use shared folders. In this case, the group admin account can create folders in its own account, then share different folders to different sub-users with different levels of access rights. When sharing a folder, you can share a folder to multiple users, sub-groups or contact groups.

By default, two group shared folders are created:

GroupRead (shared with read-only access) and GroupWrite (shared with full-access right); you can share more folders; or you can share a sub-folder in these folders. You can also share the same folder to different users and set different levels of access rights. (Just share it again using a different share name).

The shared folders can be accessed from:

\DriveHQ Share\YOUR_USERNAME\SHARE_NAME

This will save the hassle of setting up 10 individual user accounts\passwords if they are all able to connect simultaneously (if need be) to the one account login.