What do you mean? Do you intend performing this procedure on a Japanese PRS-T1? If you intend copying the partitions from one PRS-T1 to another, I guess that both must have the same version and same firmware.
In hindsight, I think that it is possible that what solved my problem was the creation of a new partition table. So you might try skipping the steps about copying partitions and simply, do a full backup, erase the partition table (the Gparted step), restore the backup just done. This might solve the problem, if your problem has a similar root cause.
In any case, if this doesn't help, you may try the full procedure, if you have access to another PRS-T1, same version, same firmware.