Hey @tfoote,
I have one question regarding ROS Ukraine group logo.
Can we create logo based on this http://www.ros.org/news/assets_c/2015/04/jadeturtle_LoRes-thumb-480x519-1116.jpg or another ROS distribution logo with Ukrainian national costume or flag for ROS Ukraine group? (we do not have any working version so far but I need to know if it is acceptable and legal to derive ROS group logo from distribution turtle image).
Thank you in advance 
Using the artwork would be fine. We make them available under the Creative Commons at artwork/distributions at master · ros-infrastructure/artwork · GitHub
However, I’d suggest that you consider a variant of the 9 dots theme with a Ukrainian flair. For example the Japanese user group has a red dot in the middle: About the ROS Japan Users Group category - ROS Japan Users Group - Open Robotics Discourse
And many of our github orgs have graphics too. There are some examples here: artwork/orgunits at master · ros-infrastructure/artwork · GitHub
It provides a nice simple way to make it your own but keep a simple consistent theme.