1) Object Repository OR is a location to save all the objects the QTP encountered during the recording phase "normal recording" it is similar to GUI map in winRunner
2)you can use insert output value then you can read that value from the global sheet and compare it to anything you want to validate it (checkpoint)
3)use the page checkpoint then edit the properties of this checkpoint under the All objects in page pan press the Filter Link button then select the 50 links you want to check in your page.
hope this will help you,
"I realize it's an error, but no one is going to try to do that!"
From "Top 10 Stupid Comments from Developers".