Cannot resize radius of a place

Hi,

Due to incomplete support of manually assigned places in Photos I am still using iPhotos. Here's my setup:

• OS X 10.11.5 El Capitan
• iPhotos 9.6.1
• MacBook Pro 17" late 2011 with 2 TB SSD and 16 GB RAM
• Magic Mouse 2

Here's the problem that I am experiencing. In Manage My Places I try to adjust the radius of a place by grabbing the <> handle of the bounding circle and dragging it left or right. When I do this, the whole map is moved left or right, including the bounding circle. This is a new problem. I am pretty sure that up to a month or so ago this was working as expected. Since then neither the version of OS X nor that of iPhotos as changed. The Magic Mouse 2 is relatively new, having replaced the Magic Mouse. At any rate, I am unable to grab just the handles when I use the built-in trackpad, too.

Any suggestions?

Thanks.