Shrewsbury goalkeeper Chris Weale fouled JP McGovern in the area on 68 minutes and Miller put United back on terms.
The game ended 2-2 but there was worse news for Carlisle with winger Matty Robson limping out of the game after only nine minutes with a suspected back problem
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Scottish leader Johann Lamont's resignation highlights the post-referendum divisions.
Remaining windy in the west. Heavy rain on Sunday morning
A consultation is to begin in Melrose to look at the possibility of charging for car-parking all year round in the town's main car park.