I am in the exact same boat as Farganger here. To what they posted, I would add that this issue is NOT specific to Apple Silicon systems.
I run HLC on both a 2017 iMac Pro and a 2020 M1 MacBook Pro. HLC crashes with the same exception on both systems after upgrading to Monterey v12.6.
I submitted a support request with the full application crash report to
support@wolflair.com. I have a LOT of non-Pathfinder content (Mutants and Masterminds in particular) that isn't accessible via HLO or HL iPad, so I hope this can be resolved soon!