There’s a bug report and discussion in Unicode about the use of Minimum Grouping Digits.
Currently unicode (ICU) defines this value for Spanish to 2, which has the effect that the thousand separator is not shown when there are 4 digits, but only when there are 5 or more digits. This means that the number “1234” is displayed as “1234” but “12345” is displayed as “12.345”. This is specially annoying in tables because numbers are not aligned as expected.
This behaviour affects Tryton at least on those users using Sao in Chrome.
I’d like to invite other native Spanish speakers to participate in the discussion in, in order to get this fixed as soon as possible. The issue was reported almost a year ago but it seems it is getting some attention now.