I have retested it with the SDG2000x definition, and there is no problem there. So it may be related to the ascii driver only.
If i use my Hameg HM8112 definition, which is very simple. And if I type askMode? , range? and intTime? on the TC command line directly, logging is not affected. Well the setup menu uses only these 3 scpiCmd's so I am puzzled.
If i invoke the Log button on TC, it will become Stop Log in red straight away. This is different when a setup menu from an ascii definition is opened/was opened. It always takes 1-2 seconds, it was always that way. It does not happen with the SDG2000x definition which is not ascii.