Might be a version issue then. Remove it and what is the exact message?
"The project you are opening uses addons that are not installed:
Behavior 'Platform MoveTo' by Rex.Rainbow
Please install the missing plugins, behaviors or effects and try re-opening the project. Note projects can be opened with effects missing. but not with plugins or behaviors missing."
Like you said it might be a version issue because i have the plugin and have used it on other projects. Any ideas how to get around this?