1) If you lose guild membership your influence marker is returned to you.
2) If you have enough status stars to gain membership in a guild, but have no influence marker, then you simply cannot become a member of the guild in question. This means no pulling, pushing, veneration points for guild membership, and the other players don't change their positions in the guild. As soon as you obtain an influence marker, however, you must immediately claim guild membership, if you still have enough status stars to do so.
Maurice is correct. : )