Yes. Generally, that is possible without any problems. There is one important thing though: You can't import files from a version newer than the version LimeSurvey is using, but usually, LimeSurvey Cloud always offers the latest stable version. Currently, you can import surveys from any LimeSurvey version 2.6+ or newer. Note that you can download any past LimeSurvey version from the LimeSurvey CE download page.