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You can show the cursor navigation wheel by tapping on the editor with two fingers.

Hello, I could reproduce the problem and have fixed the bug. It will be included in the next update.

Some background information:
IIS returns full URLs in its PROPFIND responses instead of relative paths like other WebDAV servers. This is handled by the WebDAV code, but I forgot to escape characters when the server returns paths in this way.

So for example a space character should become "%20", but that code part was missing. That's why it did work for URLs that had no characters in them that needed to be escaped but didn't work for paths with special characters.
Yes, this would be possible. I can show arbitrary content on an attached screen.

But, the use case mentioned in this idea "show source code to others in a presentation" works great with mirrored output.
I doubt that this would fit in the area above the page.
Yes, that's why I didn't add direct support in Textastic.
Sorry, but currently, there's no way to expand the file view to more than the regular 320 pixels.

You can see the full file name when you rename the file – either in the File Information popover or when you rename a file in the files view.
Currently, it looks like Textastic 3.0 will support double-byte characters and also complex scripts like Thai. I'm rewriting the code editor using CoreText.
Thanks, I'll try to find out what's going on.
I'll try to setup a test system with Windows 7 and IIS WebDAV. Do you have a link to installation instructions you followed? Just to make sure I'm using the same configuration.
Are you sure that this only happens with spaces in the folder name?

I've recently discovered another error that results in a crash when the WebDAV server doesn't send a ContentLength header. This error happens as soon as you try to download a file.