Prescaled images

Hello,

I've been working on a site that will require a vast amount of images to load and if it is true that Zencarts internal scaling of these images will eat up as much bandwidth as everyone seems to say it does, I wish to set things up to prescale the images. I'm using 3 different images (not of the same product but I figure if the site is loading different images for the same product then it couldn't be post scaling them) of the sizes 128-128, 256-256, and 512-512. The smallest is named plant.jpg; the medium is named plant_MED.jpg; and the largest is named plant_LRG.jpg. The smallest is located in the /images directory. The medium is located in the /images/medium directory. The largest is located in the /images/large directory. When I create a new product; I scroll down to the images section and click the browse button next to the first field, locating the plant.jpg file I already placed there (I'm working on a localhost) and selecting it. But when I finish the rest of the new product form, the images either don't even load, or sometimes load but post scale.

So what am I doing wrong? Is there some sort of switch in the admin console that turns post scaling off? Or am I loading the first file wrong or something? Help would be greatly apreciated.