Is there an IMS threshold that can be set for a transaction lock wait time?
I have found IMLKWAIT, but that seems to be for a job rather than a transaction.
Is this log type X'07' field DLRTMEPL in the any of the VARIABLEs of IMSTRAN?
The field you originally noted, DLRTMEPL, is what gets populated into the fields that IMLKWAIT triggers on.
The threshold would pop on any transaction that exceeds the IMLKWAIT value for a particular region and the detail record can be seen on the IMSRSLOG.
That threshold can also be triggered for a program that exceeds the value on the region even if a transaction is not involved, from what I understand, but either would be recorded in the IMS Region Summary Log (IMSRSLOG).
If you select that detail record and find the 'Locking Overview' it will provide that total lock time.