The "moslem problem" does not seem to concern the RF government at all, and the Moscow Patriarchate supports the government in all it does. The militant Muslims are treated as a case-by-case criminal phenomenon (much like Obama); the Muslim enclaves are bought off with generous budget outlays. The endless supply of low-wage central Asian workers in the big cities makes ordinary life intolerable for the plain folks, but the government refuses to even set up a vise regime. If you think our immigration policy is nuts, wait till you study RF's.
no protestant class in Russia
That is right, they are barely noticeable.
Will the Maidan movement topple Moscow from the inside
It will happen if and when the Russian people shake down their Soviet identity en masse. So far there is no evidence of that. Case in point: all these supposedly Russian patriots in Ukrainian lands bring red flags to their rallies and gather -- where else? -- in front of still surviving Lenin statues. The "nationalistic", -- for lack of better word rhetoric in RF is neo-Stalinist: "Kill the fascists", "Death to Banderovci". So is the level of their passion, -- they are barely awake and few people come to rallies. They are apathetic Sovs that wait for someone to fix their problems.
There were ethnic Russians in the Maidan. There are people of Russian origin that cheered it and are genuinely happy that at least the Ukies broke free. Also, a case can be made that Crimea perhaps needs an honest referendum and self-determination. But the statistical Russian looks like this:
Demonstration in Kharkiv (Kharkov) today, stopped in front of the city hall.
Observe: thin crowd, tired, past their prime looks. The Police Department overestimated them; a dozen cops would have been enough. One icon, one Soviet flag (inscribed: "USSR 2.0"), one Russian flag, two Ukrainian flags. A slogan: "Fascism won't pass". A photograph of the Berkut (Yanukovich's militarized police) inscribed "Berkut is the defenders of Ukraine from Fascists". Do they look like a Maidan material to you? They are still fighting WWII.
Another demonstration:
In front of the German consulate in St. Petersburg. Feel the passion?