Thanks for fixing the issue I had with Contenttweaker, sadly I ran into some others now:

The 2 Mods (Betweenlands, Erebus) I want to add Portals for right now have special rules where the Portal is generated, in specific Biomes to avoid Worldgen structures and to not block progression. Another thing is height to avoid generating the Portal underground in the Betweenlands or in the case of the Erebus, above the ceiling of the Dimension.

Could there be more options in the config files to set such restrictions?

Hmm, no promises, but I'll look into it. Again, I kinda hate my 1.12.2 codebase. 😛

Another thing... I noticed this:

"destination": {
"dimensionID": 20,
"locationDetectionBehavior": "IGNORE_INITIAL",
"initialLocation": {
"x": 0,
"y": 0,
"z": 0,
"useTopSolidY": true
},

So I want each portal to be in it's own place, obviously, but would it be possible to use TopSolidY without a specific location so players do not spawn underground? A lot of my players are struggling with that because of the darkness and caves full of monsters. The baseline Betweenlands Portal has some functionality to always place the Portal at the Surface.