Rosterr can change a person's rank in your Roblox group when you record a promotion, demotion, rank change or termination in the logbook. To do that it needs to be connected to a ranking service.
Where to set it
Settings \> Roblox & ranking. The page is called Ranking Services: "Configure external ranking services for integrated promotions and demotions".
The two options
Roblox Open Cloud: uses the Open Cloud API key you already gave Rosterr (or add one here).
RankGun: an external ranking service. You enter its API key and your RankGun workspace ID (both are required).
If neither is set up, logbook entries are recorded but no rank is changed in Roblox.
The Open Cloud key
The key lives in the same page under Roblox Open Cloud API Key. Create it in the Roblox Creator Hub, under Credentials, as a user key for your group. It needs:
group:read to read members and refresh ranks, and
permissions that allow promotions, demotions and rank changes.
Once connected you see "Roblox API key connected\!" and the last few characters of the key.
A key that only has group:read lets Rosterr read the group (this is all the set-up screen asks for). Ranking in Roblox needs the extra permissions.
Safety
Using it needs Logbook: use ranking integration, plus the matching promotion/demotion permission.
The usual ceiling applies: you cannot rank someone to a rank at or above your own unless you are an admin, and cannot rank yourself.
If the Roblox change fails, nothing is recorded.
Troubleshooting
"RankGun requires both API key and workspace ID." Enter both.
The rank did not change. The person might not be in the group, or the key lacks ranking permissions, or they outrank the account the key belongs to.
Need help? Ask your workspace admin; admins can contact Nebula support.
Related articles
Use the logbook: notes, warnings, promotions, demotions and terminations
How do I create a workspace for my Roblox group?
Mass actions on the Staff page (promote, warn, terminate, award minutes)