I have the following problem with the Mac Pro, the iPhone and the web platform:

When I add a subtask to a task that already has some subtasks, then the newly added subtask is not saved.

I added the on the iPhone and another time on the Mac. Then I synced with the server. However, the next time I open one of the Doit apps, the newly added subtask is gone on the platform where I added it and it also doesn't appear on the other platforms.

To me it seems there is an upper limit of how many subtasks one can have.