Creationists are frequently accused of using a God of the gaps argument. Such an argument boils down to we don't know therefore it must be God. While this kind of thinking has been used in the past and there are some Christians who do use it. It is not used in creation science.
The accusation of making a God of the gaps argument is frequently made by evolutionists anytime a creationist claims that the evidence actually points to God. Now sometimes the accusation is deserved but there are many times when it is not.
A proper argument showing that the evidence points to God, is not based on what we don't know but rather what we do know. For example, arguing that life had to have an intelligent designer because we know complex specific information such as that found in DNA only comes from an intelligent mind. This is in stark contrast to a God of the gaps which would be we don't know where the information came from so it must be God. The difference in this example is that in the first case we are arguing that we know where information comes from not arguing that we don't know where it came from.
In conclusion, it is important to avoid arguing for God based on ignorance. Evolutionists will often a accuse us of using a God of the gaps but we should avoid it. When you are arguing for the existence of God based on evidence or observation it is important to always use what we know whether it is from the Bible, science or even common experience rather than what we don't know.