How to restrict closure of ZMCR transactions if follow up tasks are open?

Hi CRM Experts,

In configuration, we are using copy of transaction ZMCR(copy of SMCR) and solman system is 7.1 SP 8.

We have requirement to restrict closure of ZMCR transactions if follow up tasks (which is copy of transaction type 1003) are open.

In SPRO, we did not find any option to add Task types so that status attributes can be checked under below path:

SPRO->Capabilities->ChaRM->Standard Configuration->ChaRM Framework->Make settings for Change Transaction Types.

I tried to add entries for Task types (which is copy of transaction type 1003) however it is not listed in available list of transaction types.

By default, only ZMCR and ZMCG are getting listed and not custom task transactions.

Please provide your inputs on why tasks types are not listed in above list.

Thanks in advance,

Regards,

Hanumant