After planning step by step all the details of the big day, and taking control every aspect of the wedding, now what happen to sit and relax in the great celebration?, Would be ideal, but some things can go wrong and anxiety fill and discomfort, thinking about real experiences and common situations you mentioned and warned about some things that can go more, your quiet (a), everything has a solution, just enough to be prepared.
The most common at a wedding, always be the guests of the guests, never missing a family member with many friends who think there is no problem to invite someone else to celebrate, this usually happens, we all have a family member who does not mince his acts.
For these cases, is preventable with RSVP and clear message limited capacity, or have a list of attendees for input.
If the problem has no solution soon because it is at the door asking for the bride or groom to solve the problem, you may solve the problem with a moving table, ie an additional table of 8 or 10 people "in case of emergency ". It will be easier to accommodate an extra table in some space, to reallocate space already occupied tables.
It is almost impossible to think that there will pasaditos few drinks in the evening, hopefully everyone knows behave up to the fact, in the worst case, it will be easy to convince him to go to sleep at the end of the family are all and are to enjoy not to misbehave.
Another nightmare to kill his great evening, it would be a power failure, never forget to ask if the venue has a generator that can save this situation, if not, find out from a provider with a warning that it may need, is very uncommon for this misfortune happen, but better safe than sorry.