I'm not sure I understand you completely, so I will try to explain it once again. First of all it, try not to think about it being complicated. It is simple

We have a course named 'Psychology'. The course has been split into 3 main areas:

- Introduction to psychology

- Statistical methods

- Developmental psychology

These will be 3 main chapters at root level. You can create 997 items more at root level - it could be exercises or another chapters (and in that case, it does not matter, how many subchapters or items in total they have). It could be 400 exercises and 400 chapters - it completely does not matter. The only thing that is valid is the limit of 1000 items in root level (let's name root level = level 1).

Now we enter 'Introduction to psychology' chapter and we will create items in this chapter. These items will be at level 2. Let's imagine we split the introduction into 2 subchapters: 'Introduction to psychology part 1', 'Introduction to psychology part 2'. So these will be 2 chapters contained in 'Introduction to psychology' chapter. You can create another 998 items in this ('Introduction to psychology') chapter - and again it could be both chapters and exercises. Now you can go even deeper into 'Introduction to psychology part 1' and create items inside it. The items will be at level 3. Again you can create 1000 items - exercises or chapters inside this chapter. And so on - but if you continue on creating chapters and going deeper into hierarchy, you must remember, that you can not go deeper than level 6.

Regardless of how many items you created in 'Introduction to psychology part 1' chapter, you can still create 1000 items in 'Introduction to psychology part 2'. And you can still add up to 998 items in 'Introduction to psychology' chapter.

Ok, so now we get back to root level and enter 'Statistical methods' chapter. Regardless of how many items there are currently in 'Introduction to psychology' chapter, you can create 1000 items in this ('Statistical methods') chapter - and the items will be at level 2. Again, we create 'Statistical methods part 1' and 'Statistical methods part 2' chapters. In each of the chapter we can create 1000 items (they will be at level 3) and again continue going deeper into hierarchy until level 6 is reached.

And then, the same rules applies to 'Developmental psychology' chapter.

So in conclusion you can have much more items than 1000 in one course: 1000 x 1000 x 1000 x ... etc. So all of your courses will 'fit' and you will not have to split it into separate courses.

And: the number of items contained in 'Psychology' course in total does not affect in any way the numbers of items you can create in another course.

Hope this is better explanation

SuperMemo UX uses the same mechanism to construct course tree hierarchy as SuperMemo for iPhone. The hierarchy should be replicated after synchronization, so if the course hierarchy is valid in SuperMemo UX, it will be valid in SuperMemo for iPhone.

If something is still unclear, just ask.

Thnax manicaesar. I foud your post extremely detailed and esay to understand.