I've been led to the conclusion that my internal hard disk on my 13.3" MacBook has bad blocks, despite that SMARTReporter doesn't so report, and Disk Utility sez it's OK when I run "Verify." The argument that there _is_ a problem is that when I run a piece of software it leads to some serious problems, but when I run it from a clone [made w Intego's Personal Backup], the problems cannot be reproduced, and after weeks of back-&-forths with the developer of the software, he has suggested this experiment, suspecting the Hard Disk, based on his belief that SMARTReporter and Disk Utility don't necessarily detect bad blocks, and that his software somehow depends on a bad block on the internal HD, but [of course?] not on the clone.
If all that's correct, then I would like to learn another method to test my HD, before I struggle to replace it, being out of my country, and having had a disastrous experience with a certified Apple technician who would have to do the work here.
In summary: How else can I test my internal hard disk??