What's the significance of the writing at the Dantooine Spaceport?
After several hours of searching, I cannot find any significance to these characters.
However, there is some text on the ground along the north wall that translates to "orwar for". Then there are five characters in the northeast corner, 3 of which are mirror images of Aurebesh characters that translate to "doc" and 2 that don't match any entirely but most closely resemble Enth, Thesh, Herf or Besh.
It might be that these characters represent words in the Dantari language, though being tribal it seems unnecessary to provide them with directions on the walls. Also this is unlikely because it is the only phrase posted all around the port and Basic would have a higher priority in a spaceport than the language of an indigenous, triabl people. It could however be some sort of warning to keep the Dantari away.
One theory of mine that has no basis is the possibility that these words are some sort of code used by the mercenaries or looters to communicate with like-minded travelers.
On the lore-less side, if you look at the text in the northeast corner, you'll notice that the kerning matches that of the font, suggesting it was typed and pasted onto a texture rather than drawn. This to me seems to indicate a hasty production of the spaceport resulting in meaningless text.
Furthermore, and this bit seems the most damning, if you translate the Aurebesh in Visas Marr's meditation chamber on the Ravager, it translates to "asdfasdnan", repeated over and over.