Dimensions problem.

I made a shitty flash loop and I wanna upload it on z0r, but the flash's dimensions are 700 by 400 and z0r has the default 550 by 400, is there anything that can be done?

Thank you for your time!

resize the image used in the flash

Else it will be rezised in the z0r window

set the loops background black.. the loops size will be reduced on z0r, but it will not look as shabby like this loop: http://z0r.de/2551

well the thing is there are more frames, how am I supposed to resize all of the images at once so the animation (yes it's an animation, sry I forgot to mention this) doesn't fuck up.
Do I have to do it all over again in the new dimension?