Yes, version 1.0 is too aggressive when registering supported file types. I've already changed this and it will be fixed in the next update.

For now, you can use "Get Info" in Finder and choosing a different app as the default app for all files of that type should work, too.

Textastic uses the new standard file handling in Lion and Mountain Lion.

If you click on the "File" menu and press the alt key, the "Duplicate" command becomes "Save As".

See http://feedback.textasticapp.com/topic/158682-ability-to-open-a-folder-switch-between-files-using-a-hierarchical-file-browser/

Hello, it should happen instantly. Do you have the Dropbox app installed? Did it open the Dropbox app immediately? Which part takes so long?

I don't know if it's too much to ask, but since I can't seem to reproduce it so far, it would help immensely if I could see how exactly you are using the app when it happens. So, if you happen to have a video/screen recording of the bug, that would be great.

Could you send me the files to support@textasticapp.com? Can you currently reproduce it with a different index.html file?

I've tried to do what you wrote about ten times now. It didn't happen on my device.

Which iPad model and iOS version are you using?

Does it happen every time?

Sorry, but I'm using too many new APIs that were introduced in 10.7/Lion.