Textastic uses information in the bundle's info.plist file to determine if it should load the custom bundle instead or in addition to a bundle that ships with the app. When the info.plist of a custom bundle has the same uuid as a bundle that ships with the app, the custom bundle is used instead of the integrated bundle.

If you want to use your syntax file, you therefore need to create a ".tmbundle" directory with a "Syntaxes" directory. There must be an info.plist file in the ".tmbundle" directory.

Textastic for Mac supports the same languages as Textastic for iPad. See http://www.textasticapp.com/v4/manual/lessons/Which_file_types_are_supported.html

Pascal is supported, which should work rather well for Delphi, too.

Textastic doesn't support TextMate snippets, but uses its own syntax for code completion and template files: https://github.com/blach/Textastic-Customization

Looks like I missed that behavior. I'll add it in an update. Thanks!

Thanks for letting me know. I'll fix that in the next update.

Well, it's one of the features I miss the most myself, but it's also one with many votes ;) - it's a top priority for me.