The Cromwell Mk. VI (CS) is a support tank, armed with a 95mm howitzer.
One of the British strengths in WWII was the development of specialized combat support vehicles. During WWII, 341 Cromwell Mk. VI tanks were fielded in the support role, using their 95mm howitzer against German infantry and fortifications. Often two howitzer-armed tanks were included in the command troop of a squadron along with the unit commander's Cromwell.
Like the M4A3 Sherman 105mm, the Mk. VI lacks armor-piercing ammunition and is not suited for dealing with enemy tanks, especially since its range is less than the 105mm-armed Sherman. Instead, it should be considered a support vehicle for your armor and infantry attacks, using its high-explosive shells to blast enemy troops, guns, and structures.