Translation - English-Greek - Evaluation

Car0le, this text will be used as an item for a menu, it must be as short as possible. Could you find a shorter translation ?

Bοήθεια: παρακαλώ αξιολογήστε μια μετάφραση!

For the size, that's OK. I just wander why is there a ":" inside ? (what does it mean word for word?)
By the way, you can use the "Edit" button to change it

It means "Help: please evaluate a translation!"