Perhaps you are exporting and importing the asset incorrectly. I noticed within the documentation it says, “Importing an APEX object is the same as importing a FBX file. All APEX assets are exported as .apb or .apx, Unreal Editor will determine the type of APEX object being imported.”
I am assuming you exported your asset as a .apb or .apx file as your original file for the cloth asset?
Thanks,