Re: measure unit in international role playing
I would probably express things in more general terms. Characters can be described as short, tiny, rotund, mammoth, tall, taller-than-average, a tall woman, voluptuous, solidly built, thin, slender, cadaverous, etc. Specific weight and height are probably best left to the character sheet.
As for distance and such, you can again be general, across the room, halfway down the block, a long bow-shot, pointblank, just out of reach, a few strides, ten paces (a pace being two steps), etc. You can always add a PM telling the knife thrower that the target is 'just out of range.'