Why does the Torah write "ve'es Mizbach ha'Olah Sam ... ", and not "Vayasem es Mizbach ha'Olah ... "?
Rashi (in 30:18): To extrapolate that the Kiyor was not placed in front of the Ohel Mo'ed. 1
Which Avodos did Moshe perform on the eighth day of the Milu'im?
Rashi and Ramban: Moshe performed the regular Avodah, 1 even on the eighth day of the Milu'im, after Aharon and his sons had been inaugurated, whereas they brought the Korbanos that were designated specifically for that day. 2
Targum Yonasan (at the beginning of Shemini): He no longer offered the Korbanos 3 (though presumably, he lit the Menorah and brought the Ketores as the Torah specifically states here).
Even though he was not ordered to do so here, he had been instructed to do so in 28:38 (Ramban).
See Sifsei Chachamim, who queries Rashi from his explanation in Shemini - which conforms to the opinion of Targum Yonasan. See answer #2.
It is not clear how Targum Yonasan will then explain the current Pasuk.
Which Olah and Minchah is the Pasuk referring to?
Rashi: It is referring to the Olas Tamid and the Minchas Nesachim that accompanied it.