Here is the scenario that was presented to me. Alan controls Ramos, Dragon Engine and casts Chromaticore. Nick controls Eight-and-a-half-tails he wants to turn Chromaticore white before Ramos gets counters. The question is how many counters does Ramos get?

Edited Callum Milne (Jan. 23, 2018 12:25:19 PM)

Ramos, Dragon Engine gets only one counter.

Section 608 in the Comprehensive Rules talks about how spells and abilities resolve, and one of the subrules in that section, 608.2g, describes what happens when a resolving spell or ability's effect requires information from the game. (Such as "How many colors is Chromanticore?")

608.2g reads as follows (relevant parts bolded for emphasis):

Originally posted by CR608.2g:

If an effect requires information from the game (such as the number of creatures on the battlefield), the answer is determined only once, when the effect is applied. If the effect requires information from a specific object, including the source of the ability itself, the effect uses the current information of that object if it’s in the public zone it was expected to be in; if it’s no longer in that zone, or if the effect has moved it from a public zone to a hidden zone, the effect uses the object’s last known information. See rule 112.7a. If an ability states that an object does something, it’s the object as it exists—or as it most recently existed—that does it, not the ability.

So we determine the color(s) of Chromanticore only once, as Ramos's trigger resolves, and use its current information to do so. Thanks to Eight-and-a-Half-Tails, Chromanticore is currently white and no other colors, so it's only one color, and Ramos therefore gets only one counter.

(On a side note, I've edited your post to use non-image card tags for easier reading.)