Hola, Alexei:
Lau is right.
Me gusta mucho leer. CORRECT. "I like reading very much"
Me gusta leer mucho. It would only be correct in the context of: Cuando leo, me gusta leer mucho. That is,
"When I read, I like reading a lot (of pages, books)".
No me gusta nada jugar con videojuegos CORRECT
No me gusta jugar con videojuegos nada. LESS CORRECT. Even though a native speaker would understand the sentence, the right position for "nada" is next to the word it is complementing, which in this case would be "gustar".
I hope this helps!