This includes only known jackpot (at the time of the episode) winners of all the versions and the numbers of the cases/boxes on the table on that episode.

Australia - #12
UK - #6
Philippines - #8
France (at least 5 known jackpot winners) - #20, other 4 box numbers unknown
Spain (probably more winners than that 1 listed) - #2 (very recent episode)
Brazil - #11

In all but one known case, the number on the table, which was eventually revealed to be the jackpot AND won by the contestant is even.

Has anyone else noticed the dominance of even numbers on the table when the jackpot gets hit?

The 250k when it's come to the table, even when not won here

1
2
5
6
9 - twice
10
11
12
16
18 - twice
19
20
22 - three times

It does seem that even numbers carry the 250k to the table more here.

In the US:

2 (not as the top prize)
8
11
12
17
23 ($3,000,000)
25

This seems to be the opposite over there, and in the Candian English version, case 15 brought the $1,000,000 to the table, so it seems to be different over there.