Hi Erik,
Firstly, it is possible to exempt the drums from the hold. To do this, enter C7...d
There are a number of options available and if you want to have a look at them all, right-click on the bar (in Chord Sheet View) and select "Chord Settings".

It's possible to set a chord and its play attributes on each of four beats. Select the beat (#1) and type in the chord (#2).
It's also possible to holds, rests, shots (#3) for "all instruments" or "all instruments except" (#4).
While it's not possible to get a drum break specifically, on beat 4, by putting a part marker on the bar that follows the C7...d chord, a drum break will occur in the bar (and most likely in the latter half of the bar).
Hope this helps,
Noel