Modpack Version:
1.1.2 (Luxury)

Describe the bug
Enter the Nether quest has just 1 requirement and reports as 100%
Problem is that it is outlined in blue as if there are uncompleted tasks & as a result it doesn't allow progress in any further Nether quests which also means 6 other sections can't be completed and 'Extending Reality' can't even be started.

To Reproduce
Steps to reproduce the behavior:
Visit the Nether & return (I used a waystone.)

Expected behavior
Quest completion

Screenshots

Additional context
This does not prevent any futher progress in the game... just through the questlines.

Update: After resetting the quest with the /ftbquests command, I reentered the Nether and it worked... I then had the same difficulty with the Overworld, with the same solution.

Thanks for letting me know - this has been reported by a few people, but it's still unclear exactly why this happens to some and not to most others. It's super annoying.

As you found out, it can be forced using the FTB Quests commands.

If I can ever figure out the exact cause then I might be able to fix it, but it seems to be a problem with FTB Quests picking up the advancement properly.