Duphpherer:
After you begin playing any game, immediately go back into Tapjoy/reward status. If it doesn't say "continue" then chances are you're wasting your time. They implemented this system after ripping off so many players getting told by Tapjoy that the game was not "accredited" to that player, so nothing counted.
Also, if they're not paying promptly at the first payoff point, stop playing until you see payoff.
I'm with Duph. You have to use some caution and common sense before laying out cash for any of these offers.
I only do the higher credit payout games (usually Casino or RPG), and only do the ones that allow me to make an in-game purchase for a fairly large credit reward. I like the Casino/Slots ones because there is usually an "Auto Spin" button, so I can set it for 100-500 spins and walk away.
I start of with the ones that list "Interact with the Game" or "Download the App" as the first Reward and offer some nominal amount of credits for doing this. So I'll download and play for 20-30 minutes, then shut it down and check back the next day to see if my credits are there. If they are, I keep going. If not, there's absolutely no use to waste anymore time. I'll then play long enough to reach the next level and see if that one pays. If both of those pay off, I'll feel a heck of a lot better about spending some cash. Once they pay off once or twice and you take screen shots to back your case, it's a lot harder for them to give you that run-around about "This action could not be attributed to you" or "App was not downloaded through Offerwall" once you actually outlay some real cash.
I'm currently doing a 2X Slots one and the first 2 Rewards just for opening the app and then reaching L50 both paid off (40 and 164 credits), so I'll probably do the first cash offer and see how that goes: "Spend over $9.99 in a single purchase". Then I'll wait a day or 2 to see if I receive my 4,116 credits. If that goes through I'll then do the $19.99 for 6,172, and if that goes I'll do the $49.99 for 15,432. If all goes as planned I'll get 25,720 credits for my $79.97. That's not 2X, but slightly more than 3X what I could normally buy them from WGT for ($80 = 8,000 credits). Then with the casino coins I buy I'll probably make it to the next few in-game reward levels by actually playing the game, which will get me 492, 720, and 2,468 credits before I give up. At some point I'm just going to hit the wall and not going to be able to advance any more levels.
So in the end if they keep paying off I"ll get: 40+164+4116+6172+15432+492+720+2486 = 29611 credits for $79.97 and a few hours of time (vs. paying WGT $296.11 for them).
Sorry for long wall of text, but just trying to pass along what has worked best for me the last few 2X credit offers I've done.