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Can you send me a screenshot of your FTP connection settings? Make sure that you only put the IP address in the "Host" field - do no't include "ftp://" or a trailing slash.

You can find detailed information in the manual at http://www.textasticapp.com/v5/manual/lessons/How_do_I_connect_to_an_FTP__FTPS_or_SFTP_server.html
Thank you very much! I really appreciate it.
How exactly do you try to bring up the keyboard? Please make sure that you are doing just a single tap, not a double-tap and not a long press gesture.
Update 2015-04-17: The latest versions of Textastic have the Fountain syntax definition built-in. The default themes are intended for programming languages, so you can still install and use the themes from http://www.textasticapp.com/support/FountainThemes.zip to make full use of it.

A customer also requested support for custom colors for synopses, actions and dialogue. I modified his theme and added styles for it. You can download this theme here: http://www.textasticapp.com/support/Highland.tmTheme.zip

Here's a screenshot of this theme:




You can use the theme editor at https://tmtheme-editor.herokuapp.com to modify colors (the editor requires the desktop Chrome browser).
It's great to hear that it works now!
I can only guess, but maybe Unicode characters are encoded differently than in the original file when Textastic saves them?

Also, Textastic changes all line breaks to be the same when it saves a file. Since in your case the result is CRLF (2 bytes) instead of LF or CR (1 byte), this could only result in a bigger, not a smaller file though.

To be sure, you would have to run the file through a diff program.
This looks like a network problem. Is there maybe a firewall preventing FTP network traffic? Can you try to use a different Wifi network?