Link to website HammUEr (currently Windows only) is a plugin that lets you build your levels with Valve's Hammer map editor (VMF), Doom3's DoomEdit (MAP/PROC) or an idTech2-3(Quake 1-3 and assorted other games that use the enginewith varying levels of success andnoguarantee of perfect imports)-based tool like GTKRadiant, JackHammer or Trenchbroom (MAP). With just a few simple clicks, you can have them imported into your Unreal Engine project as a collection of meshes placed in your scene the way you want, where you want. Want to change something? Make your edits in your favourite tool, then save, re-import, and you're done.