Gifts are not customary at an engagement party because they are expected at the wedding and etiquette dictates that those who are invited to an engagement party should be invited to the wedding. If you choose to give a gift you can but it is not required or expected.
If there is an engagement party then yes, the parents would give a gift. Many couples get engaged and don't have an engagement party and in this case it is not necessary for the parents to give a gift.
When I was engaged, I did not receive any engagement gifts. I do not know of any of my friends who received engagement gifts either. I think that a good replacement to an engagement gift would be a gift for their bridal shower or bachelor party in addition to a wedding gift.
No you shouldn´t. Mail them.
Unless it is the bride and groom putting on their own engagement party then they get the engagement gifts anyway. However, if it is a parent of either side of the family; relative or friend that puts on the part (they are the hostess) you do not give a gift and only need to give the future bride and groom a gift.
The couple who just got engaged could have an engagement party two to three weeks later which gives them a chance to invite guests and to give the guests a chance to set the special event aside.
Traditionally, the brides parents give an engagement party and the party is to be held in their home. Although now, engagement parties can be hosted by anyone close to the couple. Today the parties can be as formal or casual as you wish to make it. It's also becoming more common for the couple themselves to throw a "couples shower" at their home or another venue which can be much like an engagement party.
No, since you have already given an engagement gift you do not have to buy another gift for the party, but it would be a nice touch if you brought a nice bottle of wine or champagne.
No, it is not necessary to give an engagement present unless someone is giving a party for the fiance and fiancee. A wedding shower gift from the females invited to the shower and a wedding gift is etiquette.
No if anything toast can give you Heartburn.. :-(
If you are married she should already have an engagement ring. You give her the engagement ring when you propose, before the wedding is even planned.
I believe you are asking if you can give just the engagement ring and not the whole wedding set. Please clarify the question, if this is not the case. Yes, you can give just an engagement ring. Usually the man proposes with an engagement ring and then the wedding band is worn after the wedding along side the engagement ring.