Flash player older than 11.6 does not support some flags for drawing textures.
To avoid this, you should modify your (HAXELIB PATH)/hxsl/git/hxsl/Shader.hx.

(you should keep copy of the original file before you modify it)

Find following two sentences

    texHasConfig = new Vector(texSize);
    Tools.iterBlock(data.fragment.exprs, lookupTextureAccess);

and modify it to

#if flash11_6
    texHasConfig = new Vector(texSize);
    Tools.iterBlock(data.fragment.exprs, lookupTextureAccess);
#end

In addition, at the compilation stage, you should use -swf-version 11.4
in your hxml file.
