Overview
In Preview Mode when the video is played the subtitles are shown and hidden from the screen as the viewer would see them. Each subtitle appears on the screen when the current timecode reaches its in-cue and disappears when the timecode reaches the out- cue. This mode is most often used for capturing and editing the timecodes and preview of the subtitles.
When the video is played most of the commands are disabled and you can only capture in- and out-cues or overwrite existing ones using the timecode override feature (Ctrl key). All video play commands and basic navigation commands (PageUp, PageDown) are available as well but the text editing and formatting is not possible. This, however, can be changed by enabling the "Preview Mode - enable editing while playing" at Edit/Preferences/Editing menu.
When the video is paused all commands are available and you have all features from Edit mode at hand. You can edit and format the text, insert and delete subtitles, edit in- and out-cues, execute commands like Check and Fix subtitles, etc. In fact you can work entirely in Preview mode and that is the reason why "Preview mode only" option is available at Edit/Preferences/Editing.
Switching To/From Preview Mode
To switch to Preview mode press F9 (by default) on the keyboard, choose the Preview command from the View menu or press the 
button on the toolbar.
When you activate this option in Preview mode EZTitles will automatically skip through the parts of the video with no subtitles during the playback. This allows you to save lots of time during the final review by jumping over the parts where there are no conversations and subtitles. Combined with the ability to play at 1.5x or 2x speed and keep the speech understandable (Use audio time-stretch filter switched on) this could be a very powerful tool.
The Preview Subtitles option can be switched on/off by pressing the F5 button. A small indicator 
appears in the upper right corner of the video window.
The Preview Subtitles Only option has several adjustments discussed in Preferences/Command Options topic.
Timecode Commands and Timecode Override
In Preview mode, as well as in Edit mode, Num Enter, Num Ins, Num Del and Space shortcuts can be used to capture the In and Out cues of the subtitles:
Num Enter – Sets the In-Cue. If the command is executed between two subtitles, it will set the In-Cue of the next one.
Num Ins – Sets the Out-Cue. If it is executed between two subtitles, it will set the Out-Cue of the previous one.
Num Del – Sets the current Out-Cue and calculates the next subtitle’s In-Cue or sets the next subtitle’s In-Cue and calculates the current Out-Cue. This command is customizable from the Preferences/Command Options/Cues menu.
However, if the subtitles have to be re-cued in Preview mode, we strongly recommend you to do that by using the TC override commands. Press and hold the Ctrl key while playing the video and use the following commands:
Ctrl+Num Enter – Override the In-cue value with the current frame's timecode
Ctrl+Num Ins – Override the Out-cue value with the current frame's timecode
Ctrl+Num Del – This command works in TC override mode using the specified cues capture method from the Preferences/Command Options/Cues menu.
There are situations when the regular TC capture commands will not be convenient, because it may be somehow required to violate basic principles in subtitling. For example, if you need to adjust the subtitle's Out-cue to a point which appears after the next subtitle In-Cue. It won't be possible to do it without TC override because the In-Cue has greater priority and EZTitles will refuse to change it.
Snap subtitles on set In-Cue option in Preferences/Command Options/Cues can be quite useful too. If switched on, when Ctrl+Num Enter (override the In-cue command) is used and the distance between the newly set In-cue and the previous out-cue is less than the selected Snap Threshold number of frames, the previous subtitle's out-cue is moved forward to match the minimum interval between the subtitles.
Commands in Preview Mode
Most of the commands in EZTitles are disabled when you are playing the video in Preview Mode.
Exceptions are the timecode capture commands explained above and some of the navigation between subtitles based commands listed here:
PageUp – goes to the previous subtitle
PageDn – goes to the next subtitle
Alt+PageUp/Alt+PageDn – Goes to the previous/next subtitle with comment.
This is not the case when the movie is paused. You can easily edit the text in the way you need: changing alignment, delete words or whole rows, apply new presentation style, etc.