Some editor settings aren't carried over after installing Toad 10.6 and choosing to carry over settings from the previous install. Some settings had no problems being carried over, but some settings are reset. This wasn't a problem in previous versions.
The Editor Settings be set to default even when carrying over settings from a previous install to 10.6 because of changes and enhancements on the back end made to the editor and layout for Toad 10.6.
Setting reset to default will need to be manually adjusted for user preferences.
There was a similar issue when upgrading from Toad v8 to v9, because of changes and enhancements.
For more info about carrying over settings, refer to SOL42583 When upgrading or installing a new commercial version, how do you carry over settings from previous installs.