Also, when calibrating, it's probably more helpful to aim for a seconds that isn't :00. RNG Reporter generates an exception if you have the minimum greater than the maximum for Generate Adjacent Spreads, so if you're aiming for 14:00 (mm:ss) and you end up hitting 13:59, it won't show up in the adjacent spreads output, and you won't be able to check the delay\offset of the spread you got instead.
Aim for a seconds value around :20 to :40 until you consistently have your seconds calibration down. Then you can aim for numbers closer to :00.
p.s. Another tip: try to keep one NPC visible on the screen when you save. Even though my average offset when I mash A and talk to the Day Care Man as soon as the game starts is 3-4, I've been able to very consistently hit an offset of 7 if I wait for the NPC to turn or move 1 step and then immediately talk to the man. Still haven't gotten a great Chimchar yet, but it's only a matter of time.
p.s.s. After more experimenting, I've refined a technique for getting the same offset more consistently:
1) Wait for one NPC to be on screen while standing by the Day Care Man.
2) Immediately after that NPC moves, save.
3) If the NPC moves right after you save, then you can start resetting for good IVs. If not, repeat steps 1-2 until this is true.
4) Wait for that NPC to move before talking to the Day Care Man.
If the NPC was scheduled to move right after the save, then every time you reload the game, it will move at the same time. This was true when I was getting really consistent offsets of 7. Further testing will show whether or not it works most of the time.