Is the winged preset in either preset 11 or the preset 12 folder?
The winged presets need to be in one of those folders, because the .MATERIAL file is coded WITH the wing texture in the 11 and 12 folders.
Yes, it is possible to make your own meshes.
See this tutorial: http://feral-heart.com/index.php?option=com_jfusion&Itemid=2&jfile=index.php&topic=11025.0 (http://feral-heart.com/index.php?option=com_jfusion&Itemid=2&jfile=index.php&topic=11025.0)