lld for log items fails (value is not numeric) - 3.0.14

[ik_zelf]

lld array:

{ "data":[
{"{#INSTANCE_NAME}":"+ASM1","{#ALERTLOG}":"/u01/app/grid/diag/asm/+asm/+ASM1/alert/log.xml"}
,{"{#INSTANCE_NAME}":"+APX1","{#ALERTLOG}":"/u01/app/grid/diag/apx/+apx/+APX1/alert/log.xml"}
,{"{#INSTANCE_NAME}":"-MGMTDB","{#ALERTLOG}":"/u01/app/grid/diag/rdbms/_mgmtdb/-MGMTDB/alert/log.xml"}
]}

in the GUI I now get:
Cannot create item: macro "{#ALERTLOG}" value is not numeric.
Cannot create item: macro "{#ALERTLOG}" value is not numeric.
Cannot create item: macro "{#ALERTLOG}" value is not numeric.

The log item in generated using the prototype:
name: {#INSTANCE_NAME}[alertlog]
type: active agent
key: log[{#ALERTLOG},(ORA-|time=|ERROR|Dead)]

The error seems to be caused by the following prototype:
name:lines[{#ALERTLOG}]
type: calculated
key: lines[{#ALERTLOG}]
formula: {"template zbx_alertlog:log[{#ALERTLOG},(ORA-|time=|ERROR|Dead)]".count(60)}

in the formula the "log[{#ALERTLOG},(ORA-|time=|ERROR|Dead)]" is the key of the log item that is generated.

Is it possible at all to generate a calculated item that counts the # of lines received in the last 60 seconds?
If so, can you give a hint?

[ik_zelf]

I finally got this to work. In the template I added:

name: lines[{#INSTANCE_NAME},alertlog]
type: calculated item
key: lines[{#INSTANCE_NAME},alertlog]

formula: count("log[{#ALERTLOG},(ORA-|time=|ERROR|Dead)]",60)

this counts the lines that the logitem "log[{#ALERTLOG},(ORA-|time=|ERROR|Dead)]" received in the last minute.