Formlabs loves their IPA method even with all the drawbacks, Few of us have migrated to a far less toxic method you can read here: Replacing Isopropyl Alcohol with Yellow Magic
I haven’t tested Yellow Magic with castable resin but assume it would work fine. You can get YM from Z-Vat industries.
As far as the parts remaining tacky, that is actually oxidation on the resin prohibiting it from fully curing. You can easily overcome this by post curing your part while it is submersed in plain water. If you don’t have a post curing unit you can use a plastic container or ziploc bag filled with water and toss it in the sun. I use a reptile lamp that seems to work fine. There are slew of home made boxes and FL has one too.