I added the path to the models folder in WED ,but it didn't solve the problem.

But there is something I wanna ask about. When I open the Presets tab in the path section, there are three letters written between {} brackets like: WDL or MDL in front of every path ,do they indicate what the folder contain or ? Because when I add the path to the models folder, it is WDL that's written in front of the path not MDL ....