Reece Styche then sent a long-range effort over the top of goal for the hosts, before the lively Gray thought he had put his side ahead after skipping around Kidderminster's goalkeeper, only to see his effort hacked off the line by Joe Clarke.
Styche then sent an effort narrowly wide of goal when well placed and Gray curled an effort just outside the upright, but it remained goalless at the break.
There was little goalmouth action in the second half, until Kidderminster took the lead through Adam Dawson on 68 minutes.
The goal came as Tomasz Kuszczak's clearance fell to Dawson on the edge of the Birmingham area, where he calmly cut past two defenders and slotted the ball into the top corner.
However, Birmingham rescued a draw late on when former Aston Villa defender Lowry headed home a Stephen Gleeson free kick.