Thank you — I've already done that, worked like a charm 'till it came to units overlapping. For more than 3-4 units, things are getting messy very fast. And the collisions seems pretty unnatural too. But, overall the tutorial it's extremly usefull for the first steps.
irina - thank you very much for you fast reply, as well. I look forward for you to share your solution with us. It's seems like you've came up with a much better way to deal with units overlapping and movement so far. I've tried everything I can think of....and nothing.