Question: If you forget to perform b’dikas chametz and you remember on Chol HaMoed, should you wait until the night to perform b’dikas chametz or do it right away?
Short Answer: It is a machlokes when the b’dikah should be done, but most poskim say it should be performed as soon as you remember. There is also a dispute whether a brachah is recited on this b’dikah.
Question: May a shaliach eat before doing b’dikas chametz in his friend’s house?
Short Answer: There is a dispute whether a shaliach may eat before performing someone else’s mitzvah for him. Practically, it is probably better for the shaliach to refrain from eating beforehand unless he must.
Question: Should you hang a piece of your afikoman on the door?
Short Answer: There is minhag to hang a piece of the afikoman on your door for protection. Some challenge the minhag, but it is accepted by most poskim.
Question: May a person under the age of 40 publish a sefer on halachah?
Short Answer: While there was a takanah in Prague a few hundred years ago not to publish, there are many leniencies to allow a talmid chacham to publish a sefer halachah nowadays.