Images not aligning correctly

Assuming this is implemented using image size feature what you want is so-called “hard crop” mode. That will make image fit dimensions exactly, possibly cutting of their parts.

What you seem to have is soft/proportional crop mode, which tries to fit image in roughly into dimensions, while preserving all of image.

See crop mode in documentation for technical details.

If you want to get around this without messing with code, then your best option is to figure out target dimensions and upload images that have exact same ratio. That will make them fit existing setup, but is more work preparing them before upload.