When working with TemplateFinders it is important to work with the template bitmaps to make it more robust..

Editing the image in Microsoft Paint is a good way to do this. Use the image menu - Copy bitmap without graphics - to paste the template to Paint. From Paint to Scorpion use Paste the paste button 

Raw template

This is the raw resampled template.

The results is poor - 22 valves are detected.

Edited and improved template

Based on the original image a model of the valve is painted.

The results are very good - 25 valves are detected - mean score is 142 and min score is 101.