So basically when you use action script 3 you get this little errors that you fix them somehow, UDK fòrums had a thread about this, but it’s closed now, anyone remembers the key of it, or how to thanks lots. : )
Searching around i found this, with the solution down there, but there’s a lot of chinese letters : S http://www.it610.com/article/1108619.htm+
Basically if someone runs into this error again solution is easy, you go to File, Advanced Actionscript Settings
and uncheck the automatically declare stage instances.