Complex sentence: Another important issue of the campaign was the surfaced tensions between the political center and national minorities: criticism allowed, some of the minorities activists vented their protest against "Han chauvinism" which they saw in formal approach of the party officials toward the local specifics.
Split into simpler sentences: Another important issue of the campaign was the tension that surfaced between the political center and national minorities. With criticism allowed, some of the minorities' activists made public their protest against "Han chauvinism" which they saw in formal approach of the party officials toward the local specifics.