kind of hard to evaluate from the pictures, but a few things to check :
- Are all of the drawers completely flat on the bottom (put it on a known flat surface, like a countertop, and see if its truly flat)? Are the fronts and sides square, measured corner to corner?
- Is the slide hardware on the drawer box mounted exactly the same distance from the bottom of the box on both sides, and level front-to-back? It isn't something silly, like the roller is mounted upside down or something, is it?
- Is the drawer hardware on the inside of the desk mounted level on both sides, and level front to back? I like to measure my drawer slide heights from the bottom of the case, and use a plywood spacer block to position them on the sides while I install them, to ensure consistent spacing.
- Are those false fronts? Are they all square? If you get the drawers installed square to the desk, putting the drawer fronts on afterwards should be a snap with some spacers.
I think if you go back and recheck all of those things, you'll find something out of place. Square, flat drawers, installed into a square case, with the hardware all level and equidistant from the bottom of the case and bottom of the drawer box, should produce well-fitting drawers.
- Are all of the drawers completely flat on the bottom (put it on a known flat surface, like a countertop, and see if its truly flat)? Are the fronts and sides square, measured corner to corner?
- Is the slide hardware on the drawer box mounted exactly the same distance from the bottom of the box on both sides, and level front-to-back? It isn't something silly, like the roller is mounted upside down or something, is it?
- Is the drawer hardware on the inside of the desk mounted level on both sides, and level front to back? I like to measure my drawer slide heights from the bottom of the case, and use a plywood spacer block to position them on the sides while I install them, to ensure consistent spacing.
- Are those false fronts? Are they all square? If you get the drawers installed square to the desk, putting the drawer fronts on afterwards should be a snap with some spacers.
I think if you go back and recheck all of those things, you'll find something out of place. Square, flat drawers, installed into a square case, with the hardware all level and equidistant from the bottom of the case and bottom of the drawer box, should produce well-fitting drawers.