Game wise, the "canon" colors are red initially, and then blue, as far as is indicated, Starkiller's lightsaber is a single-crystal build, but in the novel, it is indicated that Kota's lightsaber is used by Starkiller after he is supposedly "killed" by Vader, with his father's blue adegan crystal. In this respect, two "canon" sources conflict, but I personally have always accepted the game as canon, where starkiller's lightsaber is in his posession until the end of the game. Canon-wise, the Dark apprentice is currently in posession of the original starkiller lightsaber, with a red synthetic crystal. Let's not forget, starkiller is deceased, and his only perfect clone was the dark apprentice as seen in the unlockable cutscenes from TFU II. Who knows, the clone who acts as the main protagonist in TFU II could always end up being the ACTUAL Galen Marek.
Who knows, a lot of facts regarding the force unleashed storyline are unclear until TFU III. Regardless, this is a wicked saber, and any who missed the first run should get in on it while they can. P.s. Include names in your paypal deposits :)