Is the cash happening when working with a song created using 3.15, when creating a new song using 3.50, or both? I don't know what plugin type you are using (VST2, AU or VST3), but for Windows 10 installs, the VST2 (just .VST extension) version of the plugin does not automatically install, you need to select it (which you have to do for Reason, which only supports VST2, not VST3).
I have an open support ticket for my crashing VST2 on Mac, but the problem there seems to be they did not include an updated VST2 plugin. The VST3 and AU work fine on Mac in DAWs that support those formats (e.g., FL Studio). The Win10 install seems to work fine.