Hello!
One easy way of removing 'black holes' is:
Mark your first clip, and click the 'A/B'-mark (Expand the Timeline if needed). You get a choise of many transitions. Mark the one on top, 'Cut (no fade)', and then go far down, 'Apply to all objects in the track'. That's it !
When cutting away parts of a clip, you should learn to use the letters D or U (in MEP 15/16). (See under the Razorblade). The black hole is filled automatically.
Try this !