Complex sentence: After the break-up of the Soviet Union, KMDB, with the Malyshev factory, became the main tank design and manufacture enterprise in Ukraine, but was still highly dependent on manufacture of components in Russian facilities, especially the Uralvagonzavod factory in Nizhny Tagil.
Split into simpler sentences: After the break-up of the Soviet Union, KMDB and the Malyshev factory became the main tank design and manufacture enterprise in Ukraine. However, they were highly dependent on manufacture of components in Russian facilities, especially the Uralvagonzavod factory in Nizhny Tagil.