I found a simple solution on the web:
http://stackoverflow.com/questions/13336153/smarty-foreach-array-sort-order
Practically it comes to replacing a line or a better option of the SQL statement that you find in the file:
Classes / specificprice.php more or less from the line # 293 (but I found it to # 599)
in this way:
change
ORDER BY `DESC id_product_attribute`, from_quantity`` DESC, `id_specific_price_rule` ASC, DESC` score`
with
ORDER BY `id_product_attribute` DESC, `from_quantity` ASC, `id_specific_price_rule` ASC, `score` DESC
there is not even need to replace the whole line just change 'from quantity' DESC, in 'quantity from' ASC,
but we must be careful not to add any other line, neither comment, nor white, otherwise it can not work, and return the white screen.
For me it worked PS 1.6.0.8 and custom template.
Bye!