Unfortunately, they can't. Each of these versions work differently enough from each other to make them incompatible. FD12's collaboration only works with FD12, FD11's only with FD11 and FD10's only with FD10.
Beyond that, each participant must have the same decimal-place version of FD -- that is, (for example) FD12.0.8 can only work with FD12.0.8, FD11.1.6 can only work with FD11.1.6 and FD10.1 can only work with FD10.1. If someone has an older build of the same version, they must update. To see if there's an update available, go to Help > Check for Updates.