You did not indicate which version of MEP that you are working with. Here is the answer for 2014:

When you insert using the import button from the arranger, the clip will be inserted wherever you have the cursor, which should be at the beginning/end of an existing clip. Other than that, see the on-line help. Select multi-track if you have objects on tracks to the right other than the track that you are inserting onto. Look up "insert modes."

Alternatively, you can drag and drop the new clip at the location (intersection of 2 clips) that you want to insert so long as nothing is on tracks other than 1 (with attached audio on 2). The clips to the right will move to the right.