How can I avoid the deformation of the first layer ?
1. Check manually the platform level.
With the printer shutdown move the carriage to the center and corners. Check distance from the nozzle tip to the plate. Use something, a credit card, between.
2. Use some adhesive over the platform before printing. Like Elmer's glue or UHU glue.
I used a very small ammount of abs diluted in acetone, works beautifully.
ABS in acetone is the best solution, fill all the little holes and you'll never have that problem again!!!
I third the ABS slurry. I keep a mason jar full around and use it before every print. Not a single issue with lifting/deformation since.
ABS slurry wasn't strong enough for me. After wasting a full spool I was finally able to keep big parts stuck to the bed. I had to fully enclose the printer and put a large bag over the top to keep in the heat. I'm attempting another print now with just the bag, but I don't know if it will retain enough heat.