RE: engine dying
Your receiver should dry out ok. The alcohol won't stay there long and castor oil is non-conductive. If you want to salvage it, open it up and rinse it out with some distilled water then leave it out in the sun for a couple of days to dry it. As long as nothing corrodes it should be fine. Obviously you'll want to do a range test and extended stick wiggling test on the ground before flying it after that.