Hossa!
Got the Jamara Me-109 "Rote Dreizehn" myself and I had the same Problems with the Wingfoil coming off. My ME - kit was over five years old before I built her and I guess the foil they used just wasn't meant to last. First flight and the tail was louder than the 15cc engine due to the free flying foil. Seeming I never liked the silver finish anyhow, I've scaled her up a bit now, oracover Foil and Airbrush "desert finish". Theres some Videos of Jamara ARF's on the German page!
www.jamara.de under "Flugvideos" in the top nav bar. especially nice the Me 109 movie!
regards,
Rev