This worked for me like a charm!Its easier t if u Followed the following method. It doesn't require any advanced knowledge.
1- Open your corrupted Nandroid Backup or the nandroid backup you just what to skip the MD5 checksum while restoring it.
2- Under your Nandroid Backup look for Nandroid.md5 file.
3- Open the Nandroid.MD5 file with any text editor.
4- Delete everything in the nandroid.md5 file.
5- Save your changes to the files.
6- Now go back to recovery and restore your Backup.
7- Done.
BTW THIS IS NOT MY FINDING, I CAN'T POSTS LINKS AS IM A NEW USE. I GOT THIS FROM ;
androidforums .com /galaxy-s2-boost-mobile-all-things-root/720978-how-remove-md5-checksum-nandroid-backup.html
What i did was, i just deleted that nandroid.md5 and then created a new file with that name, so yea basically the same thing.