The test core import has the following restriction:    "The import will not allow users to have more than a single test score per subtest imported. "

This is a defect.  The fields that uniquely identify a test are: test, subjtest and DATE:

It is perfectly reasonable for a student to have >1 scores for a particular test and subtest if they are given on different dates, (in fact, it is *very* common.)

Subjecting the person importing to this restriction is not only incomvenient , it exposes the user to a wealth of potential errors.