Take each file in the translation packand compare it to the same file name in 1.3.5, there must be diferences in the functional part of the code.

Win Merge is a free tool to assist in this comparison.

You might begin with the english version of the file in 1.3.0 and compar to 1.3.5, you will get a list of files that are different, then you only need to look at the spanish version of these files.

Many will have only comment line differences like the date created etc these are not functional