If you want to check out the differences, I've attached my encryption/decryption tool. I've also attached the source code. This tool does not fix the checksum on the save, but when I have more time, I can update it.
Edit 1 (10-29-19):
I've updated the tool to get the checksum. You still have to fix it yourself.
Code:
Switch checksum location:
File Size - 0x0c
PC checksum location:
0x04