Please use a separate feature request for each feature so that other people con vote for it. Thank you!

Yes, there is a problem in how iOS handles the preview:// URL scheme that is used for local preview in Textastic. The iOS media player seems to only support file:// and http:// urls. As a workaround, you can upload the file to a server and use the remote preview feature. 

Thanks a lot for sharing this information!

I'm currently working on Textastic for Mac and iCloud support for iOS and Mac.

Rest assured that the development of the app isn't going to stop.

You would have to transfer the source files to Textastic using one of the file transfer methods like Dropbox, (S)FTP or WebDAV. Have a look at the manual for descriptions of the various options: http://www.textasticapp.com/v4/manual/

Instead of tabs, please tap on the current file name to open a list of recently opened files:

http://www.textasticapp.com/v4/manual/lessons/How_can_I_show_a_list_of_recently_opened_files_How_can_I_close_the_current_file.html

Do you have any idea when exactly it happens so that I can try to reproduce it here? Thanks!

Yes, it is a problem with the "Open In" mechanism of iOS 6. It didn't happen in earlier versions of iOS as far as I am aware.

This is a bug in iOS 6 in combination with a duplicate definition of the .cs extension in Textastic's info.plist file. I'll fix this in the next update.

Textastic uses syntax definitions from TextMate. You can add your own custom syntax definition to the app:

http://www.textasticapp.com/v4/manual/lessons/How_can_I_add_my_own_syntax_definitions__themes_and_templates.html

Textastic uses the VHDL syntax definitions that is available at https://github.com/bpadalino/VHDL.tmbundle

You can try to add the new syntax to the language definition. The language is explained in the TextMate manual: http://manual.macromates.com/en/language_grammars