Thank you .Its as you say but just in case.
I think i fixed it.When i doubled clicked the png texture in flash i went to the action script folder and decided to uncheck ¨¨export for actionScript¨¨ and now i can import the SWF in udk without any warnings and it works.So if i understand this right,the SFW was awlays vinculated to the old name ¨¨cursor¨¨ which was the texture i was replacing and thats why i was getting that error?
Also in my foto of the flash editor>above the red square i made there is a text ¨¨ Vinculacion con AS¨¨.Which i supose it means vinculated to action script,so i double clicked it to disable it when exporting the final SWF.