I knew that already, but thanks either way. :0
I've made a couple of pokemon before, but this is the first time that it just stopped working. I always follow the same steps and it always worked, but suddenly it just stopped. No matter how many times i press L+R, the box remains empty. I tried with party slots, and nothing happened either. I've tried different combinations of pkm files, and even single pkm that have worked in the past, still nothing.
Edit:
Seems that it was L+R. The keys weren't working. Gave them a good blow and they fixed up.