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Error "-1005" is "The connection failed because the network connection was lost."

Please make sure that your internet connection is working. I'm using the official Dropbox API without modification so there shouldn't be anything different compared to Good Reader.
Note: you can "Redo" commands using the virtual keyboard: tap on the ".?123" key and then on the "#+=" key, then on "Redo".

It's a lot easier when using a hardware keyboard: use Cmd-Z to Undo and Cmd-Shift-Z to Redo.
I just tried to reproduce this: I installed EverNote on my iPad. Now I could open an HTML file in Textastic, tap on the action button and choose "Open In...". In this menu, iOS lists all apps that register itself in the system as being able to open this specific file. Then I chose "Evernote" from this menu and the file was opened in EverNote.

The system determines which apps appear in the "Open In..." menu. Each app can tell iOS which files it supports. It seems like Evernote registers itself for the necessary file types, so I could open css, txt and html files from Textastic in Evernote.

Which part didn't work for you? Did you make sure that your file has the correct file extension (.html)?
Yes, SFTP support is implemented in Textastic 2.1 and is in review.

You can vote for VGA support at http://feedback.textasticapp.com/feedback/7897-external-monitor-vga-out/ – I plan to implement this in a future update.

Thanks for your feedback!
Would it be possible to give me access to the FTP server so I can try to reproduce the issue? If yes, please send me an email.

Another possibility would be to wait for Textastic 2.1. This version is currently in review at Apple and I fixed some FTP issues there.

It could be a problem with character encoding – there is an option for character encoding for FTP connection in version 2.1 – Textastic 2.0 always uses UTF-8. Are there any files with unusual characters in the folder?

I also added a feature in 2.1 that allows you to write a debug log so I will be able to find out more by having a look at the log file.
I could certainly show a list of recently opened files in a Popover when tapping on the file name label. Also, a close button would fit nicely in there.

My problem really was how to implement this without wasting space – that's why I didn't want to have tabs (as in browsers like Firefox). I agree that this would really be a great solution.
It's implemented in Textastic 2.1 which is currently in review at Apple. See http://feedback.textasticapp.com/feedback/22877-whats-new-in-textastic-21/
Thanks! I'll try to find the cause for this behaviour.
Thanks, I'll consider it. I implemented it this way because that's how Apple's Mail implements the move command. But of course you're likely to have more file system folders than mail folders.