The FAQ said to remove Rubidium and Oculus if I wanted to run optifine instead, but it gets stuck loading on the main menu forever when I try to do that! :( not sure what I'm doing wrong...

Found it thank you, I really hope the issue isn't just that I'm not waiting long enough. latest.log

If we assume that :

• you're using curseforge
• the user on your computer is named to2oro
• you named your curseforge profile Bliss

Then you will be able to find a file named latest.log at C:\Users\to2oro\curseforge\minecraft\Instances\Bliss\logs.

You may need to remove something else. Can I see your game log?

Er, as soon as I figure out where that is ^^; it isn't crashing/creating a crash log, if that's what you mean.

First action:
[14:41:03] [main/INFO]: ModLauncher running

Last action:
[14:49:07] [Worker-Main-12/INFO]: [OptiFine] BetterGrass: Parsing default configuration optifine/bettergrass.properties

Your action:
[14:55:53] [Render thread/INFO]: Stopping!

It looks like there was 8 minutes of intense mod loading (14h41- 14h49).
Then you decided that 14 minutes of loading time was a weirdly long loading time (14h41 - 14h55).

I don't understand what optifine was doing during these 6 minutes (14h49 - 14h55), since there are no more logs for that time period.

Could you please try to load again the modpack, with the same configuration, but this time with more time to load (like 30 minutes) ?

Because optifine stopped to say things in the logs, and there are no crashes, it's hard to understand clearly what's happening.

Um... yeah, the issue was just patience. Sorry. I overreacted because the loading times were longer than running it as default and the progress bar stopped abruptly.