I've figured it out. Here is the code:
Dim dBT As Object 'global dictionary
Sub buttonpresscount()
'constants for column positions
Const COL_BLOCK As Long = 1
Const COL_TRIAL As Long = 2
Const COL_ACT As Long = 7
Const COL_AOI As Long = 8
Dim rng As Range, lastrow As Long, sht As Worksheet
Dim d, r As Long, k, resBT()
Set sht = Worksheets("full test")
lastrow = Cells(Rows.Count, 3).End(xlUp).Row
Set dBT = CreateObject("scripting.dictionary")
Set rng = sht.Range("B7:I" & lastrow)
d = rng.Value 'get the data into an array
ReDim resBT(1 To UBound(d), 1 To 1) 'resize the array which will
' be placed in ColT
'get unique combinations of Block and Trial and pressedcounts for each
For r = 1 To UBound(d, 1)
k = d(r, COL_BLOCK) & "|" & d(r, COL_TRIAL) 'create key
dBT(k) = dBT(k) + IIf(d(r, COL_ACT) <> "", 1, 0)
Next r
'populate array with appropriate counts for each row
For r = 1 To UBound(d, 1)
k = d(r, 1) & "|" & d(r, 2) 'create key
resBT(r, 1) = dBT(k) 'get the count
Next r
'place array to sheet
sht.Range("T7").Resize(UBound(resBT, 1), 1) = resBT
'clear dictionary
dBT.RemoveAll
'count AOI entries
For r = 1 To UBound(d, 1)
k = d(r, COL_BLOCK) & "|" & d(r, COL_TRIAL) 'create key
dBT(k) = dBT(k) + IIf(d(r, COL_AOI) = "AOI Entry", 1, 0)
Next r
'populate array with appropriate counts for each row
For r = 1 To UBound(d, 1)
k = d(r, 1) & "|" & d(r, 2) 'create key
resBT(r, 1) = dBT(k) 'get the count
Next r
'place array to sheet
sht.Range("U7").Resize(UBound(resBT, 1), 1) = resBT
End Sub
I basically duplicated the previous code, added another constant for the relevant column and changed the relevant references to columns, and made sure to clear the dictionary inbetween counting tasks.