I am having the same issue. After adding exception, either through the Firefox window or by bringing up the settings (TruClient General Settings) window and adding it that way. Can also be added by importing the cert in the settings window. The certificate gets added but seems to require a new script to be started fresh and recorded. If attempting with an existing script the "this connection is untrusted" window keeps appearing even if the exception/cert has been added. Re-recording after adding the new cert/exception is the only way I've found to get around this issue. Kind of a pain when you have to re-record after the cert expires every 6 months or so.