Colin,
Thank you a lot for sharing your findings!
I suspected that extensions should slow-down tests run speed, but have never hit such big time differences like you did. Maybe this is because I never used some technologies supported by TestComplete and always turned off the relevant extensions every time when I upgraded TestComplete.
Considering your results I would like to vote for (Tanya, your attention, please):
a) All extensions should be enabled when TestComplete is installed a-new;
b) With no test project opened the state of extensions should be stored as the default project properties;
c) Extensions state should be a per-project setting and stored in the main project file (I don't think at the moment that extensions state should be different if the project is opened in the networked mode);
d) If TestComplete is in the version upgrade mode and installs a new extension, this extension should be enabled in the default project properties. Obviously, this new extension should be available from all already existing projects, but I am not sure whether it should be enabled or not in them.
Alumni