Using JR East pass in Matsumoto

I will be using a JR east pass to go to Matsumoto. The online timetables are saying that I can catch a ＪＲ特急ワイドビューしなの12号 from Nagano to Matsumoto, which per my understanding is a wideview train. According to JR site, "In such cases, passengers must pay fares and charges applicable to the distances traveled on respective railway company. The following are names of JR EAST trains that enter the lines of other railway companies: ... Wide-view Shinano..."
Could you please advise whether I need to pay extra to catch this particular train and if so, how much?

The Shinano limited express is between Matsumoto and Nagano is completely covered by the JR East Pass.

Moomoocow,

My understanding is that the Wide View Shinano runs for the most part in the JR Central area, so the JR East Pass will only be valid for the short section from Matsumoto to Shiojiri. If you enter Shiojiri to Nagoya in a site such as Hyperdia, it should tell you how much you will have to pay. Depending on the answer, you may want to consider getting a full Japan Rail Pass instead.

Thanks for your help.

I won't be heading to Nagoya. furthest I'll be is Matsumoto, I'm happy that it's all covered by JR East pass.