Currently http://openra.res0l.net uses a self-patched version of Tao for correct 64-bit support which seems not actively maintained anymore for years. OpenRA uses Tao for FreeType, SDL, Cg, OpenGL and OpenAL. http://www.opentk.com/project/about says it supports FreeType, but I can't find something like Tao.FreeType. Also Cg seems to be missing and OpenTK.Compatibilty seems incomplete for OpenAL because I get many errors like
`OpenTK.Audio.Alc' does not contain a definition for `alcOpenDevice'
The name `Al' does not exist in the current context
By the way: would there be much benefit switching from Tao to OpenTK? Will this fix existing rendering issues with OpenGL at Intel cards (that's why they added Cg support).