Topological Semigroups and Universal Spaces Related to Extension Dimenion

It is proved that there is no structure of left (right) cancelative semigroup on [L]-dimensional universal space for the class of separable compact spaces of extensional dimension  [L]. Besides, we note that the homeomorphism group of [L]-dimensional space whose nonempty open sets are universal for the class of separable compact spaces of extensional dimension  [L] is totally disconnected.