I too have an issue with getting my MCP-combo (v1) to work in XP10.2 (64-bit). After Google'ing and reading here and on the Vrinsight's website, I thought I knew what to do, but...apperantly not.
I have installed the VRiSim v1.0: it detects my MCPcombo. I select "MSFS Original aircraft".
I installed XPUIPC v2.0.0 in XP, but I never saw anything regarding VRinsight in any menu items in XP, not even under the Plugins. When trying to add a button or such in the 'Joystick & equipment' is futile :(
The XPUIPC plugin shows as active
The MCPcombo is showing SPD, HDG and ALT, so...there is some kind of connection between the VRiSIM and the MCPcombo. I just don't understand why XP isn't connecting aswell.