I have just started using my m3D and had some of the same problems. Different colors seem to work differently. Black onyx seemed to work best for me but I had been printing on lowest res just for trial prints. Some prints came unstuck and after I used some glue craft stick it worked well. I also found out I needed to be sure the head was heated properly before I start and the filament needs to be coming out of the nozzle before starting a run. I wanted to see how well it would do on something extremely complex (took 10 hours to print a lacy bracelet) That print had some very fragile areas that broke when I tried cleaning it up but I believe I can use pieces for some jewelry. The best print I have gotten so far was a solid miniature chair. I tried some more delicate chairs at 1/2 size (1:48" scale) and they are extremely fragile Thinking I might be able to strengthen them using CA glue. Will experiment with that. I have been feeding the spools externally and thinking of printing a spool holder. The inexpensive machine has limitations which I can live with because I want to print very small items and obviously there will be a lot of experimentation, trial and error. Keeping it simple is the best advice until you learn with it (I didn't quite take that myself) but I am having fun with it and so far am pretty happy with it. Good luck, be persistent. I have only printed using the program that sets the temperature automatically for each filament spool. As long as it feeds well before I start it seems to work okay.