Could anyone please advise as to whether Allaston and Allaston Meen are the same place or 2 different places?

Effectivly the same part of Lydney; if you want to split it further the Meend is the Common
belonging to Allaston
http://www.geograph.org.uk/photo/2729401

Allaston Meend, comprising a compact area south of the house called Soilwell and a long roadside strip extending down Primrose hill on the road to Newerne

From: 'Lydney', A History of the County of Gloucester: Volume 5: Bledisloe Hundred, St. Briavels Hundred, The Forest of Dean (1996), pp. 46-84. URL: http://www.british-history.ac.uk/report.aspx?compid=23251 Date accessed: 21 December 2012.