Vladimir:
It is no more worrisome to burn incense sticks before an Icon than it would be to spray Febreeze in front of one; they're purely aromatherapeutical. They aren't "blessed" or "cursed" or anything else. Only a priest of the true religion of God has the power to genuinely bless anything, in any case; anything else is utterly impotent and meaningless. A circle of voodoo witches could stand over the incense sticks, sprinkle them with the blood of a dead black cat, and chant a curse over them at the stroke of midnight and it wouldn't do anything to them (apart from make them unsaleable, what with all that blood sprinkled all over them).
As far as icons go, they aren't the icons of heretics, mind you, but the icons of artists. The work comes from the talent of the artist and not from the heresy of a sect he may belong to. We could just as easily ask if the frescoes of men who were not in the state of grace may adorn our churches, or if the music of hypocrites may be permitted in our liturgy. So-called "Protestant" hymns make their way into Traditional Catholic worship all the time, I notice. Pope Pius VII was patron of the famous Lutheran sculptor Thorvaldsen who sculpted a celebrated statue of the pontiff and an even more celebrated statue of our Lord, the "Christus Consolator". The heresy of his sect had nothing to do with his remarkable talent or his art, however. Could a statue of a pope ever be called a "Protestant" statue, just because it was sculpted by the hands of a man identifying himself as a Protestant? No, of course not. Then why a tune by a composer? Is an Icon any different?
I think you're safe on all counts.