Observed location of bug:
com.mindfusion.common.BaseList.remove(Object)

Condition for reproduction:
List does not contain the element to be removed.

Observed behavior:
Method throws java.lang.ArrayIndexOutOfBoundsException.

Specified behavior (per java.util.Collection.remove(Object)):
Method returns false.

Tested with:
JPlanner 2.1.3

Stacktrace:
java.lang.ArrayIndexOutOfBoundsException: -1
     at java.util.ArrayList.elementData(ArrayList.java:424)
     at java.util.ArrayList.remove(ArrayList.java:501)
     at com.mindfusion.common.BaseList.doRemove(Unknown Source)
     at com.mindfusion.common.BaseList.remove(Unknown Source)

Reproducing unittest:

import static org.junit.Assert.assertFalse;

import com.mindfusion.common.BaseList;
import org.junit.Test;

public class BaseListTest {

    BaseList<Object> sut = new BaseList<Object>() {
        //
    };

    @Test
    public void test() {
        // Given
        final Object o = new Object();

        // When
        final boolean actual = sut.remove(o);

        // Then
        assertFalse(actual);
    }

}