Since updating to 9.0.2.421 Captivate locks up and I have to reload the program

As RodWard​ says, you should verify the preferences and cache files were handled correctly.

Compare your process with the details in the release notes from the Captivate update files.

In another thread, Re: Sluggish performance after update pbdw1969 suggested:

Follow the steps as outlined in the release notes for the update.

You may also want to clear out your cache.

To clear your cache, with Adobe Captivate running but no projects open...

1. Click Edit / Preferences (Shift + F8)
2. Click on the General Settings category
3. Click the Clear Cache... button
4. Click OK

Did you reset the Preferences and Layouts folders when you updated?

If not, Google for Captivate 9.0.2 Release Notes and read the instructions about updating.