Epoxy tends to work better on hinges that have a pinned hinge. there are also "CA" hinges designed to work with thin CA (cyanoacrylate). These are fitted into the wood parts dry, then the thin CA is dripped into the very small gap between surfaces. I prefer the CA hinges for any plane under 12 pounds

Most use bolts and nuts to hold the engine to the mount. Vibration here can cause wood screws to come loose. Use the nuts with the plastic inserts that keep them from loosening.