The way I use Stackz is to have a set number of words to learn in a given time period, and then put them in my Review stack, which I test several times a week. So, when I have long lists of words to learn (for example, for JLPT2) I first randomize them and break them up into weekly "lessons." Then I learn one lesson per week (usually 100 words or so) and at the end of the week I copy-paste that entire lesson into the Unknown bin of my Review stack.
The problem is, what happens when I want to go back and add more cards to those lessons? For example, right now I have a certain number of weeks until JLPT2. So, I broke up all of the words I need to learn into that number of lessons. But, occasionally I'll find a nice wordlist online, for example the onomatopoeia list, and I want to distribute that evenly among my current lessons.
It would be a simple matter of copy and paste, but the problem is, Stackz doesn't let you remove focus from the Edit window when you're in it.
So, instead of: Highlight words in the onomatopoeia list, Ctrl+C, selecting a lesson stack, Ctrl+V...repeat...
I have to: Edit list, Highlight words, Ctrl+C, Save, Close edit window, Select Lesson Stack, Ctrl+V, Select new list...repeat
I know it doesn't sound that annoying, but it is!!!
Anyways, it would be nice to be able to select another stack while having the edit window open.