A Bishops of Opposite Color Ending

From time to time I enjoy going over my old games with an engine just to see how I did back in the old days.  More often than not it’s disappointing because games I thought were well-played had some serious errors.  The following ending, which arose from a Ruy Lopez Marshall Attack, was disappointing because I thought I should have won despite the ending with Bs of opposite color.  As it turned out my judgment was correct…Black should win from the starting position. Generally though the ending was pretty well-played by both sides.