The Riftbreaker is (was?) my favourite game of all time, with just under 300 hours recorded on it.
However, with this last addon - which I gladly paid full price for! - I can't get through the VERY FIRST core game level without it freezing (NOT slowing, FREEZING!) into a total lock-up.
This was with the latest June 7th (2023) patch (with both addons, custom in-game difficulty, and a few in-game downloaded mods).
(However, even with the above, I'm still going to buy all upcoming addons - I just might have to wait till I get a new computer before playing them!)