I have been trying to name my new enchanted weapon, but when I complete the enchantment, the item either does not appear in my inventory or the name simply stays the same... is this a common bug ?!

Did you hit enter after naming?

took me a while to figure it out...

after selecting item,enchantment, and gem...

use mouse to click lower left 'use F to rename'.
you should then be able to type in the name window.
when finished click enter to confirm name.
you then click 'r' to finish enchantment... click 'o.k.' to confirm.

Yeah I have to press Enter on the keyboard after naming... it worked

thanks