how to run under win7
Try to use the instruction in the FAQ, which is located in discord community. # faq chanel
Can you explain in fews words (or with a link), why we have to install Sentinel ? what is the use ? What is it doing ?
Sentinel appeared in DASH in update 12.1. And since WAVI is a fork of DASH, the respective requirement of Sentinel migrated to our network. Now MN should function without Sentinel, but in the future, when the DASH V13 update is released, it may become necessary. In that case, if WAVI receives this update we will definitely have to use Sentinel.
On the question why need Sentinel, you can find information on the DASH forums. Example:
https://www.dash.org/forum/threads/what-is-sentinel-masternodes.13063/In brief: "The Sentinel update adds new features to the platform. It also optimizes existing internal protocols, management, voting and privacy characteristics."