Is it possible to downgrade my forum back to a earlier version, from 4.5.2 back to 4.4.10 ?

Short of creating your own migration script, the only way to revert to a previous version is to restore from the backup of the filesystems and database you took just before upgrading. This means that any changes, new content (new posts), etc. will be lost and things will be back to what it was when you took your backup.

Ok thats what I thought thank you.