Hi Mikhail. Welcome to G2G!
The family tree of Edward III must be gigantic, much bigger than the 10,000-person limit on a GEDCOM export. Even with that limit, the file may be so large that timeouts are not surprising.
The question is, why do you want this? As Maggie has said, it's more usual for beginning WikiTree members to add their own family trees, working backwards though time, until they connect up with profiles that already exist.