Three people have specifically said, in response to your post, that you haven't completed the steps. The instructions are provided in the first post, and Archeia even quoted them in her response a few posts above.
What you have done by applying the update is to update MV - the editor. What you have not done yet, and still have to do, is manually update any existing projects.
When you apply the update, it affects the editor and any new projects you create. If you already have existing projects, they will not be updated unless you do it manually. To do this, you need to copy away your plugins.js file to a safe location so it won't be overwritten, go into the MV program folder and find the newdata folder, then copy the js folder inside that and paste it into your project. This is what updates your project to 1.3.3. Then you get your plugins.js file from the safe place you put it so it wouldn't be overwritten, and you paste it back into your project (because the plugins.js file from the newdata/js folder would have replaced it, so you need to put your plugin settings back). Finally you need to see if all your plugins still work - some of them may have been broken by the update, and if they were, you need to get new versions of those plugins.
Everything you need to know has now been provided. You need to follow the steps to update your project.
Edit - either I didn't see the other posts, or they were made while I was writing this. If you've now followed the process to update your project and are getting an error, it's very likely that you have a plugin that no longer works with 1.3.3, and you need to start working through them to figure out which one it is. In that case, your questions no longer belong in this thread, because the update of MV and of your project is complete. Hitting F8 will give you the programmer's console, where you will see more information about the error, and you can then post a screenshot in a new thread in the JS/Plugin Support forum to get help for that plugin.