Hi, I had this problem before, I just solved it yesterday. Actually the .dae and .rcdone files are not necessary for the model, as long as you have a .cgf file. But I guess it did not create any .cgf file for you, if this is the case, try the following: 1. Download a plugin called"CleanUp" from sketchucation forum, it will check validity of planes, edges and fix them for you, sometimes this works. 2.Your model might contain too many vertices or entities, Playup has a limit of 64000 vertices and around 1200 entities, try to divide your model into several small groups; 3.If you could not split your model, then you might need some other exporter, eg, from 3ds.Max to cryengine, like what I did..Goodluck