How do you know if the process has worked or not without testing pkg?
In step 5, when you enter the content-id; if you get error messages, mean that sectool is not able to perform the resign on the pkg.
If not there are any errors your pkg will work perfectly.
PS: atm, i get this error on gaia manager, ps3usercheat and PSIDpatch.
release pseusercheat worked for rogero 4.21 CFW
ps3usercheat (signed by Luis)