Here's the way I would calculate, in case it helps...
Let's look at Timings in column "15K".
H:
Display Time: 47.40~50.99us
No Display Time :12.50~16.20us
Bporch: 4.7~8.4us
Sync: 5.0+/-1.52us
Fporch: NDT - Bporch - Sync
V:
Display Time: 220~240 lines
No Display Time: 23~43 lines
Bporch: 16~24 lines
Sync: 2~6 lines
Fporch: NDT - Bporch - Sync
Everything looks variable here so let's choose a starting point.
Let's say 320x240@60, since the specs show total line value of 263 then Hfreq = 60x263 = 15780 Hz = 15.78 kHz
so total H time = 1000 * (1/15.78) = 63.37us
If we set Bporch = 5.98us (ok with 4.7~8.4us), Sync = 4.78us (ok with 5.0+/-1.52us), Fporch = 4.78us
then NDT = 15.54us (ok with 12.50~16.20us)
and DT = 48.83us (ok with 47.40~50.99us)
-> (rounded) H timings: 4.8,4.8,6.0
For V timings let's choose Bporch = 16, Sync = 4, Fporch = 3
We need values in ms so:
Bporch = 16/15.78 = 1.014ms
Sync = 0.253ms
Fporch = 0.190ms
-> V timings: 0.190,0.253,1.014