01Where the Config Editor lives
The Config Editor opens from the active profile and lists the configuration files r2modman knows how to read for the packages installed there. Editing happens in the profile, so the values you see belong to that mod set rather than to the game as a whole. Whether two profiles stay independent depends on where the mod writes its file, so check the profile name in the header and the path the editor is showing before assuming a change is isolated. Save the file before switching profiles, and take an export from Settings → Profile → Export profile if the change matters.
02Change one value per launch
Edit a single setting, save, and launch before touching the next one. Two simultaneous edits make it impossible to tell which value produced a new behaviour, and if the game refuses to start you have no way to narrow the cause. For a value you care about, note the package version and the original text first, because some options accept only a specific unit or range and a number that looks reasonable can be out of bounds. Revert the single change rather than editing further when the result is wrong.
03Flag settings that affect other players
Some options reach beyond your own machine. Server rules, network behaviour, world generation, difficulty and key bindings can affect other players or persist across sessions. When you change one of those, note why the non-default value exists and whether every participant needs it. A value that is harmless in a solo world can desync or be rejected in a shared one, and a setting tuned for one connection can be unforgiving on another. If you share the profile, mention the changed settings alongside the code, because an export carries supported configuration with the package list.
04An empty editor proves nothing
A blank Config Editor does not mean a mod has no configuration. Some packages write JSON, YAML, databases or custom formats that the editor never reads, and others have not created a file yet: a BepInEx plugin generates its config on the first modded launch, so a fresh install can list nothing until the game has run once. When a package you expect is absent, launch as modded once, check the profile's data location, and read the mod README for the real file name and format before editing anything by hand.
05What the editor will not do for you
The Config Editor is a text editor for supported files, not a compatibility layer. It does not explain mod-specific options, does not validate every value you can type, and cannot repair a plugin that fails to load. A syntactically valid file can still be semantically wrong, because the manager has no way to know that a multiplier is meant to stay between 0 and 1. Keep the mod README or the Thunderstore page open when units, ranges or multiplayer effects are unclear, and treat the author's documentation as the description of record.
06Recover from a bad configuration
If a change breaks the launch, restore the copy you made or disable the package you just edited, then confirm the game starts again. To find the responsible value, export the profile from Settings → Profile → Export profile, import it into a second profile, and reintroduce changes there one at a time. Do not delete the profile, reinstall the game and clear the cache in one pass; that destroys the evidence you need and turns one bad value into an evening of rebuilding. A profile export taken from Settings → Profile → Export profile before the edit is the fastest route back to a known state.
07A concrete case: the BepInEx console
One setting worth knowing is the BepInEx console. In some games it opens a terminal window that takes controller input, so the game launches but no button press reaches it. Open the BepInEx core configuration, disable the console, and launch with Start modded again. Reach that file through the Config Editor when it is listed, or through Settings → Directories → Data and profile folders → Profile folder → Browse when it is not. That same configuration also controls logging verbosity and other loader-level behaviour sitting underneath every plugin, which makes it a sensible first stop when input or startup misbehaves.
✦ Frequently asked questions
Common questions, answered directly.
Does the Config Editor back up my changes?
No. It writes to the file and shows you the result. Copy an important configuration file or export the profile before changing many values; a profile export records supported configuration as it stood when you took it, but the editor itself keeps no history.
Why is a mod missing from the Config Editor?
The package may not create a supported configuration file, it may write JSON, YAML or a database the editor does not read, or it may not have run yet. Launch the game as modded once so a loader such as BepInEx generates its config, then look again.
Are config changes shared between profiles?
It depends on where the mod writes its file. Confirm the active profile in the header and the path the editor is showing before assuming a change stays inside one profile. Some packages resolve paths relative to the game directory instead of the profile.
Can the editor fix a mod that will not load?
No. It edits configuration text for supported files. A plugin that fails to load needs the loader log, correct dependencies and a matching game build; changing values will not repair it, and the editor cannot tell you which plugin threw the error.
What if a value I type is rejected?
The editor does not enforce every range, so a value can be accepted and still be invalid at runtime. Restore the original text, check the README for accepted units, and change one setting per launch so the cause of a new behaviour stays obvious.
Each step on this page ends in a result you can see before the next one starts, so a failure points at one layer instead of the whole stack.
Next: download or update the current build, keep one profile with only the loader enabled, confirm a modded launch from Start modded, then add the rest of your mods in small batches.