Sorry for a late reply! So basically, in C4D once you add first texture to any material in scene, c4d creates a 'tex' folder in the same location where the file istelf is stored, then that file looks for all the textures in that tex folder no matter what, and it is not showing any file paths in texture slot, just the name. On the other hand IES file is not recognized by name, but by full path instead and if I move my whole project with tex folder to desktop for example and open it, all textures are read fine, but IES file is missing, since there is no more IES in that particular path. In Vray it works the same way textures do work, if I move my project with tex folder, IES file is recognized no matter what, since C4D file is looking for it in TEX folder. Hope Im clear here. Thank you for your work guys!