Hello, where can I download the original flash files for T4240QDS?
Answer could depend on meaning of the word "original" which you assume.
One of the factors is that during board manufacturing current Linux SDK is used to create NOR Flash image, so there could be different images in the boards from different batches.
Do you have U-Boot log for your board?
Alternatively you can download one of e6500 IMAGE ISO of the latest Linux SDK from:
https://nxp.flexnetoperations.com/control/frse/download?element=7726177