Ironically enough, I was able to get the BC-IC Crossover working again - removing it, loading the world, then exiting and re-adding the mod. It did mean I lost the machines, but I can build new ones.
The add-ons that no longer work (and crash the game) are, as you said, the ones that require recharging - for me, that's More TreeTaps and Thermometers. I am uncertain about Advanced Generators - I only use it for the miner (and I'd like the pump) but I don't need the other machines in it and would like to spare the block IDs. Waiting for the next release of that add-on, apparently the pump and miner will be available separately.
So in the end, most of the 1.23 add-ons are compatible - though they may require removal and re-installation.