The DITA Task Topic is limited in it functionality but as mentioned in the previous message you can add additional levels to your Procedure Heirachy using a DITA Map containing a series of Tasks. For example the Section 1 and Part 1 above could be from the DITA Map Structure containing groups of Tasks.

DITA Task Topics only have 2 levels of Steps within a Topic, Steps and Substeps. You can add to this using the DITA Specialization or you can put Ordered Lists inside the elements allowed inside Steps and Substeps like <info>.

I Hope this helps.

It's hard to know without knowing more about your specific docs, but if what you have labeled as "Step A" really has steps and substeps under it, my instinct is that "Step A" is really a task topic and what you have as Part 1 is a sequence of tasks (Step A, Step B).

You might have to put a little work into recreating your original presentation using this pattern for topics, but it can certainly be done.

But in general, using your existing print presentation conventions as you move to DITA for technical content usually makes things harder. Better to take a step back and try to determine what the content is really doing, map that to DITA (which should be a cleaner and more direct mapping) and then see how close that can get back to your original presentation conventions (and also decide if you an opportutity to develop more effective presentation conventions).

The work Seth Park has done at Freescale to emulate their legacy print manuals from very sophisticated DITA content shows it can be done, but they put a lot of effort into it, merely to avoid trying to have a conversation about changing legacy presentation approaches at the same time they were changing legacy source and authoring processes.

Cheers,

Eliot