I used the Import spreadsheet to import my Skills but nothing imported - what could be wrong?

Make sure that all the Skills you are importing have unique names.  If there is already a Skill in your database with the name "Skill1", you will not be able to import another skill with the same name.  Also, remember that each main Skill must have a row all for itself with no Subskills listed.  Any Subskills for that main skill must be listed underneath in their own rows.