How many level of sub-categories supported?

How many level of sub-categories supported?

For example:
Level 1 - Financial Services

Level 2 --Investigation Services
Level 2 --Investment Services

Level 2 --Leasing Services
Level 3 ---Financial Consultants
Level 3 ---Money Managers
Level 3 ---Venture Capital

When I use the "[dr_list_categories style="grid"]" command, I can see my main categories (Level 1) and (Level 2), but I can't see any of my sub-categories (Level 3) ...

Is there any way to display my Level 3 sub-categories?