Adding a timer object to a scenario group address

Hello KNX supprt

I am trying to add a switch actuator timer object to a scenario group object, this timer object is to have a light automatically turn off after 5 minutes from turning it on by calling the group object with a push button on a 4 button KNX switch.

This function is achievable when I add the timer object to a group object containing switching objects, but it will not be added to a group object containing scenario objects, and an error message appears saying that:(The group address cannot be linked with the group object. The object size differs.).

As the message says the object length for the timer is 1bit, while the scenario group objects have a length of 1byte.

Also I tried to search the data types for the timer object and it doesn't contain an 8bit or a byte scenario type.  

Is there a way to change the timer object data type to 8bit length to be able to add it to the scenario group object?

Or kindly point me to a workaround to achieve this function.

Thank you in advance for your help.

Khaleel Alshaer