Layout Editor can't add some module block.

[joebordes]

It won't break the crm, it may change some behavior but you MUST do this every time you update to keep your database in sync with the code. In other words, after you update your code (git update) you MUST load and apply all changesets.

You can read about this functionality and how amazing it is in the blog: http://blog.corebos.org/en