Please help us help you and fill where relevant:
Your LimeSurvey version:3.22.28
Own server or LimeSurvey hosting: Own
Survey theme/template: vanilla
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We have a survey in 12 languages. We wanted to have group relevance equations that are the same for all languages (in fact, I was under the impression that grelevance always applies to ALL languages), but they seem to only work for the base language (in this case English). We are updating the grelevance through the RemoteControl2 API, but I don't think that's relevant, since the other languages also remain without a group relevance when you try to update through the GUI. Attached is an example group. Is this a bug or am I doing something wrong? Thanks for your help!

Never upload a LSQ or LSG, but always a simplified LSS. Help us to help you.

LSQ and LSG are language sensitive. Not only would the helpers have to create a survey (and for LSQ also a group) to import the LSQ/LSG file to, they would also have to guess the base language correctl. You mentioned it is English, so this helps. But it is always better to make a copy of your LSS, delete all unnecessary parts and export it.

Also your version LS 3.22.28 was released 28/07/2020 which means it is almost 2 years old. A lot can have happened since then and if it is a bug it might be long fixed. So ideally you first update to the latet version and then check if the problem persists.

since the other languages also remain without a group relevance when you try to update through the GUI.

This is not reproducable. Works as expected (tested in 3.27.19 and 3.27.33)

And you'd better shown how you try to update the group relevance through the RemoteControl2 AP

Joffm