Are there any alternatives to deleting frames (permanently)?
When editing, I often want to hear/see what it *would* look like if I deleted some frames, before actually deleting them.
For example, it would be good if you could mark frames as 'skip', so that you can preview an edit before actually deleting frames.
At the moment, I'm having to rely on the undo button if I don't like the result of my frame deletion.
There's nothing like that available at the moment, I'm afraid. Its the first time we've had it requested but perhaps it is something we could consider for the future.
What I do is to start a second instance of Flashback, which I then use as a temporary scratchpad area to copy and store frames, and anything else I need to re-use.
As far as I can see you can't "cut" frames (CTRL-X), but you can copy and paste them to the other instance before deleting them. If you don't like the result, you can copy and paste them back. This is safer than relying on undo because you can copy stuff in any order and if necessary save it in a file.
You can't do anything with the other instance of Flashback until you have opened an FBR file in it, but it can be any dummy file which you keep for the purpose.
An alternative to that is the File > Save Selected Frames to New Movie function. After deleting the frames, if you don't like the result you can Insert > Flashback Movie to restore them.