If you need to insert a new subtitle text box, you can do so by following on of the below steps:
Add at Current Time
With the player position at the precise point you wish to insert a new title, select the "Add at current time" button.
The in cue of this new subtitle will match the position in the player.
The duration and out cue of this new title will be determined by the 'Duration of title' setting.
This can be found within Options / Preferences / Edit menu, and default value set here is 2 Seconds.
You can then amend the out cue as required.
You can also use a keyboard shortcut to efficiently add a new title to the list. Default keyboard shortcut is the 'Insert' key.
Add after Last Title
To insert a new title after the last title in the current list, you can select "Add after last title" button.
This will insert a new title after the last title in the list.
The gap between the new and the existing last title will be determined by the 'Minimum gap to next title' setting. This can be found Within Options / Preference / Title Validation menu. Default value here is 2 frames.
The duration and out cue of this new title will be determined by the 'Duration of title' setting.
This can be found within Options / Preferences / Edit menu, and default value set here is 2 Seconds.
You can then amend the out cue as required.
You can then amend the in and out cue as required.
You can also use a keyboard shortcut to efficiently add a new title after the last in the list. Default keyboard shortcut is the 'Shift + Insert' key.