Biter Refugium 3 requires both "Optimized Biome Planner" (Dark Green) and "Burns-out QL Bio-Processor" (Dark Purple), however, the lab (Quantum Interactions, 3rd tier) that supports dark purple science doesn't have a slot for the Dark Green Science. Thus it's seemingly impossible to research this tier (and thus about 16 subsequent techs)

Thanks for reporting this! I'll have a look tonight

This is caused by a bug in Science Cost Tweaker. As a temporary workaround, if you manage to unlock Lab 2 - this will take all science packs.

Thanks. I have it unlocked, but haven't quite gotten advanced circuits done yet, at least I know that getting those done will let me get past the limitation

Fixed in ScienceCostTweaker Mod (mexmer) version 1.1.6

Note that version 1.1.2 added an additional ingredient to Blue (Chemical) science packs.