I bought a starter solution which is on filemaker 13 but I am using Filemaker 12. Now when I am editing the layout, it constantly crashes or hangs with not responding error and Runtime error. What should be my next steps.
The biggest difference between FM12 en 13 in the layouts are:
Object visibility control
All of these are not available in FM12 and if they are used, you won't be able to edit them nor will you see the side-panels and popovers. Hidden object will not be hidden in FM12, causing lots of problems.
Your best option is to upgrade to at least FM13, but better to FM15.