[stavros]

Ex* nihilo.

[globnomulous]

The 'x' is omitted when the following word starts with a consonant. The only places where you're likely to find counterexamples are in poetry, where breaking the rule can be metrically expedient.

[valleyer]

Both are accepted. See one of the mottos of the US, "e pluribus, unum".

[stavros]

Ah, I see, thanks.