Hi Dave,
The module is not designed to work with CR2032 (or other battery). It is better to use small battery, let said 150mAH, which is almost the same size as the CR2032 (and smaller that CR2x2032)
Forcing voltage on VIN as high than 6V (2 times CR2032) will probabely be kiling for some part when you are going to connect the USB (for downloading your FW for example).
Rgrds.