Grouping items using an identifier

I'm creating a model for a client that has a list of actions that they want grouped together based on their focus. I've put in identifiers to help with the grouping, but I'm having trouble illustrating it the way they want while still have it automatically compile itself. There are three levels, with each action lumped together at two higher levels (illustrated by the identifiers: the first number is the highest level, second the middle, and so on). So, here is how the list would look with only the identifiers:

1.1.1
1.1.2
1.2.1
1.2.2
2.1.1
2.1.2
2.2.1
2.2.2

The problem is that they need to be grouped together by all possible levels and illustrated that way, updating automatically. The ideal end state for the above example is this:

1.0
1.1
1.1.1
1.1.2
1.2
1.2.1
1.2.2
2.0
....

Now, the big kicker is this: I can't use any VBA or macros. The client refuses to change their security settings for fear of spreading some imaginary virus (I'm not kidding).

Where I am getting hung up is actually getting the actions to list themselves: with VBA, it'd be very easy to setup a for loop or something like that, but without it I'm stuck.

Any ideas?

It seems like both of your lists are grouped in the same manner... will there always be 3 digits in each action?

A sample workbook upload would be a great help.

I'm working on creating the sample workbook as we speak.

The actions are the most basic levels and they just roll up into higher classification, so they will always have that "three digit" code. Mind, I created that code so it would be easier to group: originally, it was just a list of actions that I have a hardcopy of.

Attached is a quick example of what I need: everything else I have completed or can do and this is the only interaction I'm struggling with.

The scorecard has to update automatically, so the size of the array is variable. Thanks for any advice.