Some offers take a little longer to credit then others and unfortunately sometimes a couple wont credit at all but I have found that 85% of the time they do credit. I would say give them a few days to credit if they are from the SPECIAL OFFERS you can send a ticket and if you can prove you completed it they will credit you for them. You can find this in the OFFER STATUS section OF THE special offers section
http://www.fusioncash.net/specialoffers.php Some of the videos have been really delayed lately but they will credit eventually took mine a few days.
The offers that say "check account instead" are usually SURVEYS like the dailies. Those in my experience credit every time you complete them if you qualified for them.
Sometimes it is a good idea to not complete to many in a row make sure you clear your cookies before you start a new one and don't rush through them some offers have timers.
If you see an offer that you haven't completed in that list it means you clicked on it. It is jsut a list of clicks not necessarily something you followed through.
Hope this have been helpful. For more answers and info feel free to ask any time and check out my guide :
FLOREZITTA'S BEGINNERS GUIDE to FREQUENTLY ASKED QUESTIONS
http://www.fusioncash.net/forum.php?topic=15241.0