Veresov,

Most of the mods were stuck in 1.2 I believe, not 1.3. Wasn't really much reason for them to go to 1.3 since it had some serious defects that made a further patch likely. Modding for 1.3 on a major mod didn't make much sense. Afterall, there were a lot of supporting tools that had to be migrated as well. Many deficiencies in 1.2 that had been compensated for by mods would have to be reworked.

Hopefully, 1.5 will settle the matter by completing RTW as much as can be expected. Then I think you will see most major mods migrate to it. A good patch will be a no-brainer move.