In the Questions section of the Marketplace plugin page, Microsoft said that the reason 5.1 is taking them so long is that they want to address the user complains of poor performance on larger projects with many blueprints before they release it. So even if it worked when recompiled, I still think it’s a good idea to wait for the official 5.1 version 
At the same time, it is quite frustrating that the plugin release is not synced with engine release, as the UE IDE support seems to come with VS by default, so this breaks the precedent of things always working at least reasonably well out of the box