"There are those who would disagree. Yushchenko supporters have been pretty vehement in denouncing the Yanukovych camp" -- Yanukovich supporters have been denouncing the Yuschenko camp in much the same words. However, I don't see a question of "Why did Bush feel the need to derail the election?" in your post. And I don't see allegations of fraud made by the Yanukovich camp appear in Western media. For example, did you know that of the about 11,000 complaints of voting irregularities filed with the CEC, most came from Yanukovich?
"Again, this is an oversimplification." -- how is it an oversimplification? You asked why people in different regions support their candidate, and I told you what Ukrainian voters think. Do you really believe that an average voter considers all the power blocs and who he wants to align himself with? Such considerations should be left to political so-called "scientists"...
"Well, there may be an element of prevarication at some levels, but to my mind it is more a case of incompetence, ignorance of the issues involved, laziness in choosing not to delve into the underlying issues..." -- if that were the case, western media would at least attempt to be objective, giving equal coverage to both sides, even if that coverage were ignorant. However, what I see is simple propaganda for one side, which incidentally happens to be the side receiving generous financial support from various western governments. So this disingenuity is not accidental, it is simply the media taking a political stand in support of their respective governments. Freedom of speech does not imply honesty of speech. Chomsky was right.