After installing this with GameStages, the mod crashes on startup, with this error:

[13:24:52] [Render thread/FATAL]: Mixin apply failed resourcestages.mixins.json:MinecraftMixin -> net.minecraft.client.Minecraft: org.spongepowered.asm.mixin.transformer.throwables.InvalidMixinException @shadow field pendingReload was not located in the target class net.minecraft.client.Minecraft. No refMap loaded.

latest.log

Am I supposed to run the game with just GameStages before, and after creating the stages, adding this mod?

Forge - 43.3.0
Version: 1.19.2

GameStages-Forge-1.19.2-11.1.5.jar
resourcestages-1.19.2-1.1.jar

Oh, the refmap didn't generate again.... Try fixed version: ResourceStages 1.1.1. On CurseForge, there will be an update a little later

And you also forgot to install KotlinForForge.

Yeah, didn't crash now

Is KotlinForForge a dependency?

Oh actually, it is installed

Yes, since the mod itself is written in Kotlin, you also need to install a library to support it.
I take it the problem has been solved?

Yes it loaded! But I found a new crash while testing the mod in-game, should I open another issue?

I can write you on discord, maybe it's better?

All right, then let's do it that way