AlgoWizard Actions are completely erased after specific action is taken

This wasn't easy to isolate :) Please resolve when you can.

Steps to reproduce:


1. Load the attached Bug.sqx file
2. Go to the "Config Trend" tab
3. Go to the last "Assign Variable" with all the summations
4. Right click at the end of the formula and choose "This element +"
5. Choose the Double variable TrendWeight9
6. Save the file (i.e. as Bug2.sqx)
7. Go back to the "Config Trend" tab
8. Note that all variable assignments are gone :(