Hello!
Thank you for reporting it. We had that issue in version 1.1.0.

If you haven't updated to version 1.1.1-beta, you can get it here:
https://sketchucation.com/forums/download/file.php?id=148934

Tell me if the problem resolved after update

Hi! Report any issues you have with the FlexTools plugin - I'll be glad to fix them.
Adding your operating system, SketchUp version and other extra information would be of great help.

I hope our plugin will improve your workflow