So, because turning off IC2 rubber gen in 1.97 crashes at startup with this error I posted on the support thread:
I've been playing with 1.95b. And I found that turning off IC2 rubber gen in 1.95b deletes the recipe of converting Propolis (from the bees of forestry) to resin. If I turn it on again, it works fine.
I'm assuming it would still have the same problem in 1.97, so I'm just reporting it. And sorry for being persistent about this, some may think it's a useless feature, or nothing to worry about, but I quite like it, so it's sad to see it broken.
Hope the next patch comes soon!