I'm looking at your data set, and I've add a few columns to help me see the number patterns. N is the track number (5-232), O is the target level, and P is the difference between your level and the target. This reveals a pattern of -1s and -2s similar the the pattern of +12s and +13s.
The pattern for the last cycle, tracks 204 to 232, is the same as the previous cycle (175 to 203). This would indicate that nothing changed in last cycle, so let's not worry about those tracks for now.
The pattern for cycle 146 to 174 doesn't match cycle 175 to 203. The +12 occurs on track 186 instead of 187. This would seem to indicate that a tiny fraction was dropped somewhere between track 158 (row 236) and track 186 (row 268). The most suspicious looking tracks are the last few completed with the RSC - Autumn Ring mini through Beginner. Several of those tracks tend to be a little stubbon (maybe High Speed Ring, rows 241, 242, 267, and 268). This point is likely to be too small to be detected when collected unless it's the very last point.
The pattern for cycle 117 to 145 matches the pattern for cycle 175 to 203 and this seems to extend back to track 100 (row 172). These track seem to be complete: 100 to 158, and 187 to 232.
On track 86 you were are at -0 but missed the milestone at 8125 by -1. Something is missing before then. I suspect this is a fairly large fraction because you still earned +12 on the next race and stay at -1 for the next few races. Then on track 94 you drop to -2, so points have definately been lost somewhere between track 87 and 94. Also, the data for 95 to 99 is useless - I can't tell anything with the small data set.
It looks like you were quite thourough in your A-D/World Again search. Earning points on InSt and TRMS with the MX-5 explains most of my suspicious data. The only number that might be out of place is the +12 on HoKR with the Lupo - maybe recheck tracks 61 to 73 with the MX-5.
Best Guess Summary
Large fraction before track 87 (8125)
* Maybe the MX-5 (A), tracks 61 to 73, rows 121 to 135
* Points might be missing on more than 1 track
Large fraction between tracks 87 and 100, rows 159 and 166
* MX-5 SC (B), maybe recheck tracks 95 to 100
* Points might be missing on more than 1 track
Small fraction between track 158 and 186, row 236 and 268.
* RSC Driving Park 1st, then Original Circuits,
* Also HSR+R with MX-5 SC and Driving Park with 350Z LM
For clarification: I cannot apply math to the fractions to be more precise. Strange things happen when the fractions resolve which makes estimating the size of a fraction and predicting +12 very difficult.
It looks like you are missing 2 points on at least 3 tracks, so earned fractions may be hidden. Chart and save all the +0 tracks. It's up to you to consider resetting after a +1 track in order to determine which tracks were actually hiding the points.