Hi again,

I'm still working on Textmate to Geany color schemes conversion and I like to show you some effects. I also want to ask you for help and contribution, because at this stage, work is more time consuming and arduous.

Here is a converter written in Ruby. This is a Geany theme writer's module, only this file is necessary for you:
https://github.com/ciembor/coloration/blob/master/lib/coloration/writers/geany_theme_writer.rb

As you can see, there are mappings of TextMate properties in format:

"geany_property" => @items["some_property"] || @items["alternative_property"] || @items["etc"] || "emergency_geany_property"

And here are some (over 250:)) TextMate themes with equivalents for Geany:
https://github.com/ciembor/TextMate-Themes
https://github.com/ciembor/geany-themes/tree/master/colorschemes

But it's not easy to find accurate properties in TextMate. I didn't found any documentation. Worse still, I have no Mac :D. The only way is to read theme after theme, try new mappings and compare them with screenshots:
http://textmatetheme.com/

Any remarks are welcome. You may put them on this mailing list or here:
https://github.com/ciembor/coloration/issues

Cheers
- Maciej Ciemborowicz

P.S.
One more thing. Some properties, like colors of line numbering are not existing in any TextMate theme :(. I still consider the best solution.