The traditional D&D alignments system is a great tool for character development. Choosing a character’s place on the scale of Good & Evil (altruistic to selfish) and the scale of Lawful & Chaotic (social to independent) can really help a player to determine motivations and responses for that character. It is a very useful starting place, but should remain a springboard and not a straitjacket.
In the Nomm campaign setting, alignments will have no mandatory consequence in the game mechanic and little tangible effect in the game logic. Weapons will not be aligned as Good or Evil and have their use restricted to characters with the correct alignment; deities will not require any particular alignment of their cleric, since gods have no alignment (see Religion tab); magical rooms will never admit only Good characters while forbidding entry to Evil characters, or if they do, selection will be based on the perceptions of the controlling mage rather than the notes on the character sheet. Clerics will find that the domains of Good and Evil might be a little extraneous, since, for example, spells that target Evil creatures may or may not work on any individual specimen of a class – you see, alignments will not be assigned categorically to monstrous humanoids and monsters, but individually.
So, by all means, be prepared to select an alignment, to use it as a base for building a character, and to role-play the alignment appropriately to earn bonus RP-XP. Your alignment will, however, be a mutable personality trait rather than some sort of deterministic, fundamental quality.