president and vp not at meeting

A} Can the president appoint a alternate vice president in advance
B} or would the remaining board memebers have to select an acting
president to fill the role at the time of the meeting

Is it my understanding that the directors can have a 1st and 2nd vp>
In which case the 2nd would head the meeting

If your bylaws do not specify a 2nd VP then there is no such office, unless your bylaws permit the board to create offices that are not enumerated in the bylaws. Roberts Rules (10th ed) states this on page 436:

"If the president for any reason vacates the chair or is absent, the vice-president or first vice-president normally should take the chair unless he also, because of involvement in the debate or for any other reason, should disqualify himself from presiding in the particular case; and if the first vice-president is absent or must disqualify himself, the duty of presiding devolves on the other vice-presidents in order. For this reason, the bylaws should number the vice-presidents if there are more than one, and persons should be elected to specific positions."

In no event, does the president have the authority to appoint someone to preside in his absence or the absence of any vice president.

As stated previously in this thread, if the president and (all) vice presidents are absent, the proper procedure under Roberts Rules is for the secretary to call the meeting to order and as the first item of business the members elect a president pro tem who presides for that meeting. If the secretary is absent, any member may call the meeting to order, followed by the election of a president pro tem.